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597fa65373
print out ldr, not ldr.n. rdar://problem/9267772 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130008 91177308-0d34-0410-b5e6-96231b3b80d8
1812 lines
59 KiB
C++
1812 lines
59 KiB
C++
//===------------ ARMDecoderEmitter.cpp - Decoder Generator ---------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file is part of the ARM Disassembler.
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// It contains the tablegen backend that emits the decoder functions for ARM and
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// Thumb. The disassembler core includes the auto-generated file, invokes the
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// decoder functions, and builds up the MCInst based on the decoded Opcode.
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//
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//===----------------------------------------------------------------------===//
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#define DEBUG_TYPE "arm-decoder-emitter"
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#include "ARMDecoderEmitter.h"
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#include "CodeGenTarget.h"
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#include "Record.h"
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#include "llvm/ADT/StringExtras.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/raw_ostream.h"
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#include <vector>
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#include <map>
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#include <string>
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using namespace llvm;
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/////////////////////////////////////////////////////
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// //
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// Enums and Utilities for ARM Instruction Format //
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// //
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/////////////////////////////////////////////////////
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#define ARM_FORMATS \
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ENTRY(ARM_FORMAT_PSEUDO, 0) \
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ENTRY(ARM_FORMAT_MULFRM, 1) \
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ENTRY(ARM_FORMAT_BRFRM, 2) \
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ENTRY(ARM_FORMAT_BRMISCFRM, 3) \
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ENTRY(ARM_FORMAT_DPFRM, 4) \
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ENTRY(ARM_FORMAT_DPSOREGFRM, 5) \
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ENTRY(ARM_FORMAT_LDFRM, 6) \
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ENTRY(ARM_FORMAT_STFRM, 7) \
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ENTRY(ARM_FORMAT_LDMISCFRM, 8) \
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ENTRY(ARM_FORMAT_STMISCFRM, 9) \
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ENTRY(ARM_FORMAT_LDSTMULFRM, 10) \
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ENTRY(ARM_FORMAT_LDSTEXFRM, 11) \
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ENTRY(ARM_FORMAT_ARITHMISCFRM, 12) \
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ENTRY(ARM_FORMAT_SATFRM, 13) \
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ENTRY(ARM_FORMAT_EXTFRM, 14) \
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ENTRY(ARM_FORMAT_VFPUNARYFRM, 15) \
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ENTRY(ARM_FORMAT_VFPBINARYFRM, 16) \
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ENTRY(ARM_FORMAT_VFPCONV1FRM, 17) \
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ENTRY(ARM_FORMAT_VFPCONV2FRM, 18) \
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ENTRY(ARM_FORMAT_VFPCONV3FRM, 19) \
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ENTRY(ARM_FORMAT_VFPCONV4FRM, 20) \
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ENTRY(ARM_FORMAT_VFPCONV5FRM, 21) \
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ENTRY(ARM_FORMAT_VFPLDSTFRM, 22) \
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ENTRY(ARM_FORMAT_VFPLDSTMULFRM, 23) \
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ENTRY(ARM_FORMAT_VFPMISCFRM, 24) \
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ENTRY(ARM_FORMAT_THUMBFRM, 25) \
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ENTRY(ARM_FORMAT_MISCFRM, 26) \
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ENTRY(ARM_FORMAT_NEONGETLNFRM, 27) \
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ENTRY(ARM_FORMAT_NEONSETLNFRM, 28) \
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ENTRY(ARM_FORMAT_NEONDUPFRM, 29) \
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ENTRY(ARM_FORMAT_NLdSt, 30) \
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ENTRY(ARM_FORMAT_N1RegModImm, 31) \
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ENTRY(ARM_FORMAT_N2Reg, 32) \
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ENTRY(ARM_FORMAT_NVCVT, 33) \
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ENTRY(ARM_FORMAT_NVecDupLn, 34) \
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ENTRY(ARM_FORMAT_N2RegVecShL, 35) \
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ENTRY(ARM_FORMAT_N2RegVecShR, 36) \
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ENTRY(ARM_FORMAT_N3Reg, 37) \
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ENTRY(ARM_FORMAT_N3RegVecSh, 38) \
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ENTRY(ARM_FORMAT_NVecExtract, 39) \
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ENTRY(ARM_FORMAT_NVecMulScalar, 40) \
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ENTRY(ARM_FORMAT_NVTBL, 41)
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// ARM instruction format specifies the encoding used by the instruction.
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#define ENTRY(n, v) n = v,
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typedef enum {
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ARM_FORMATS
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ARM_FORMAT_NA
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} ARMFormat;
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#undef ENTRY
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// Converts enum to const char*.
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static const char *stringForARMFormat(ARMFormat form) {
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#define ENTRY(n, v) case n: return #n;
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switch(form) {
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ARM_FORMATS
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case ARM_FORMAT_NA:
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default:
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return "";
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}
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#undef ENTRY
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}
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enum {
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IndexModeNone = 0,
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IndexModePre = 1,
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IndexModePost = 2,
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IndexModeUpd = 3
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};
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/////////////////////////
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// //
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// Utility functions //
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// //
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/////////////////////////
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/// byteFromBitsInit - Return the byte value from a BitsInit.
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/// Called from getByteField().
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static uint8_t byteFromBitsInit(BitsInit &init) {
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int width = init.getNumBits();
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assert(width <= 8 && "Field is too large for uint8_t!");
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int index;
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uint8_t mask = 0x01;
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uint8_t ret = 0;
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for (index = 0; index < width; index++) {
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if (static_cast<BitInit*>(init.getBit(index))->getValue())
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ret |= mask;
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mask <<= 1;
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}
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return ret;
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}
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static uint8_t getByteField(const Record &def, const char *str) {
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BitsInit *bits = def.getValueAsBitsInit(str);
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return byteFromBitsInit(*bits);
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}
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static BitsInit &getBitsField(const Record &def, const char *str) {
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BitsInit *bits = def.getValueAsBitsInit(str);
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return *bits;
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}
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/// sameStringExceptSuffix - Return true if the two strings differ only in RHS's
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/// suffix. ("VST4d8", "VST4d8_UPD", "_UPD") as input returns true.
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static
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bool sameStringExceptSuffix(const StringRef LHS, const StringRef RHS,
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const StringRef Suffix) {
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if (RHS.startswith(LHS) && RHS.endswith(Suffix))
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return RHS.size() == LHS.size() + Suffix.size();
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return false;
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}
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/// thumbInstruction - Determine whether we have a Thumb instruction.
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/// See also ARMInstrFormats.td.
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static bool thumbInstruction(uint8_t Form) {
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return Form == ARM_FORMAT_THUMBFRM;
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}
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// The set (BIT_TRUE, BIT_FALSE, BIT_UNSET) represents a ternary logic system
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// for a bit value.
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//
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// BIT_UNFILTERED is used as the init value for a filter position. It is used
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// only for filter processings.
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typedef enum {
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BIT_TRUE, // '1'
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BIT_FALSE, // '0'
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BIT_UNSET, // '?'
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BIT_UNFILTERED // unfiltered
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} bit_value_t;
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static bool ValueSet(bit_value_t V) {
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return (V == BIT_TRUE || V == BIT_FALSE);
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}
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static bool ValueNotSet(bit_value_t V) {
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return (V == BIT_UNSET);
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}
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static int Value(bit_value_t V) {
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return ValueNotSet(V) ? -1 : (V == BIT_FALSE ? 0 : 1);
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}
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static bit_value_t bitFromBits(BitsInit &bits, unsigned index) {
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if (BitInit *bit = dynamic_cast<BitInit*>(bits.getBit(index)))
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return bit->getValue() ? BIT_TRUE : BIT_FALSE;
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// The bit is uninitialized.
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return BIT_UNSET;
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}
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// Prints the bit value for each position.
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static void dumpBits(raw_ostream &o, BitsInit &bits) {
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unsigned index;
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for (index = bits.getNumBits(); index > 0; index--) {
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switch (bitFromBits(bits, index - 1)) {
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case BIT_TRUE:
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o << "1";
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break;
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case BIT_FALSE:
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o << "0";
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break;
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case BIT_UNSET:
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o << "_";
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break;
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default:
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assert(0 && "unexpected return value from bitFromBits");
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}
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}
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}
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// Enums for the available target names.
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typedef enum {
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TARGET_ARM = 0,
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TARGET_THUMB
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} TARGET_NAME_t;
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// FIXME: Possibly auto-detected?
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#define BIT_WIDTH 32
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// Forward declaration.
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class ARMFilterChooser;
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// Representation of the instruction to work on.
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typedef bit_value_t insn_t[BIT_WIDTH];
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/// Filter - Filter works with FilterChooser to produce the decoding tree for
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/// the ISA.
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///
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/// It is useful to think of a Filter as governing the switch stmts of the
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/// decoding tree in a certain level. Each case stmt delegates to an inferior
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/// FilterChooser to decide what further decoding logic to employ, or in another
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/// words, what other remaining bits to look at. The FilterChooser eventually
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/// chooses a best Filter to do its job.
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///
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/// This recursive scheme ends when the number of Opcodes assigned to the
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/// FilterChooser becomes 1 or if there is a conflict. A conflict happens when
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/// the Filter/FilterChooser combo does not know how to distinguish among the
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/// Opcodes assigned.
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///
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/// An example of a conflict is
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///
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/// Conflict:
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/// 111101000.00........00010000....
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/// 111101000.00........0001........
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/// 1111010...00........0001........
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/// 1111010...00....................
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/// 1111010.........................
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/// 1111............................
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/// ................................
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/// VST4q8a 111101000_00________00010000____
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/// VST4q8b 111101000_00________00010000____
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///
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/// The Debug output shows the path that the decoding tree follows to reach the
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/// the conclusion that there is a conflict. VST4q8a is a vst4 to double-spaced
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/// even registers, while VST4q8b is a vst4 to double-spaced odd regsisters.
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///
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/// The encoding info in the .td files does not specify this meta information,
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/// which could have been used by the decoder to resolve the conflict. The
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/// decoder could try to decode the even/odd register numbering and assign to
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/// VST4q8a or VST4q8b, but for the time being, the decoder chooses the "a"
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/// version and return the Opcode since the two have the same Asm format string.
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class ARMFilter {
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protected:
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ARMFilterChooser *Owner; // points to the FilterChooser who owns this filter
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unsigned StartBit; // the starting bit position
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unsigned NumBits; // number of bits to filter
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bool Mixed; // a mixed region contains both set and unset bits
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// Map of well-known segment value to the set of uid's with that value.
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std::map<uint64_t, std::vector<unsigned> > FilteredInstructions;
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// Set of uid's with non-constant segment values.
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std::vector<unsigned> VariableInstructions;
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// Map of well-known segment value to its delegate.
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std::map<unsigned, ARMFilterChooser*> FilterChooserMap;
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// Number of instructions which fall under FilteredInstructions category.
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unsigned NumFiltered;
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// Keeps track of the last opcode in the filtered bucket.
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unsigned LastOpcFiltered;
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// Number of instructions which fall under VariableInstructions category.
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unsigned NumVariable;
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public:
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unsigned getNumFiltered() { return NumFiltered; }
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unsigned getNumVariable() { return NumVariable; }
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unsigned getSingletonOpc() {
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assert(NumFiltered == 1);
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return LastOpcFiltered;
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}
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// Return the filter chooser for the group of instructions without constant
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// segment values.
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ARMFilterChooser &getVariableFC() {
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assert(NumFiltered == 1);
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assert(FilterChooserMap.size() == 1);
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return *(FilterChooserMap.find((unsigned)-1)->second);
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}
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ARMFilter(const ARMFilter &f);
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ARMFilter(ARMFilterChooser &owner, unsigned startBit, unsigned numBits,
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bool mixed);
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~ARMFilter();
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// Divides the decoding task into sub tasks and delegates them to the
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// inferior FilterChooser's.
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//
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// A special case arises when there's only one entry in the filtered
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// instructions. In order to unambiguously decode the singleton, we need to
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// match the remaining undecoded encoding bits against the singleton.
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void recurse();
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// Emit code to decode instructions given a segment or segments of bits.
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void emit(raw_ostream &o, unsigned &Indentation);
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// Returns the number of fanout produced by the filter. More fanout implies
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// the filter distinguishes more categories of instructions.
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unsigned usefulness() const;
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}; // End of class Filter
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// These are states of our finite state machines used in FilterChooser's
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// filterProcessor() which produces the filter candidates to use.
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typedef enum {
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ATTR_NONE,
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ATTR_FILTERED,
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ATTR_ALL_SET,
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ATTR_ALL_UNSET,
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ATTR_MIXED
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} bitAttr_t;
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/// ARMFilterChooser - FilterChooser chooses the best filter among a set of Filters
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/// in order to perform the decoding of instructions at the current level.
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///
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/// Decoding proceeds from the top down. Based on the well-known encoding bits
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/// of instructions available, FilterChooser builds up the possible Filters that
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/// can further the task of decoding by distinguishing among the remaining
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/// candidate instructions.
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///
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/// Once a filter has been chosen, it is called upon to divide the decoding task
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/// into sub-tasks and delegates them to its inferior FilterChoosers for further
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/// processings.
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///
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/// It is useful to think of a Filter as governing the switch stmts of the
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/// decoding tree. And each case is delegated to an inferior FilterChooser to
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/// decide what further remaining bits to look at.
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class ARMFilterChooser {
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static TARGET_NAME_t TargetName;
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protected:
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friend class ARMFilter;
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// Vector of codegen instructions to choose our filter.
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const std::vector<const CodeGenInstruction*> &AllInstructions;
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// Vector of uid's for this filter chooser to work on.
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const std::vector<unsigned> Opcodes;
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// Vector of candidate filters.
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std::vector<ARMFilter> Filters;
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// Array of bit values passed down from our parent.
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// Set to all BIT_UNFILTERED's for Parent == NULL.
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bit_value_t FilterBitValues[BIT_WIDTH];
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// Links to the FilterChooser above us in the decoding tree.
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ARMFilterChooser *Parent;
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// Index of the best filter from Filters.
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int BestIndex;
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public:
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static void setTargetName(TARGET_NAME_t tn) { TargetName = tn; }
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ARMFilterChooser(const ARMFilterChooser &FC) :
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AllInstructions(FC.AllInstructions), Opcodes(FC.Opcodes),
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Filters(FC.Filters), Parent(FC.Parent), BestIndex(FC.BestIndex) {
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memcpy(FilterBitValues, FC.FilterBitValues, sizeof(FilterBitValues));
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}
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ARMFilterChooser(const std::vector<const CodeGenInstruction*> &Insts,
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const std::vector<unsigned> &IDs) :
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AllInstructions(Insts), Opcodes(IDs), Filters(), Parent(NULL),
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BestIndex(-1) {
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for (unsigned i = 0; i < BIT_WIDTH; ++i)
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FilterBitValues[i] = BIT_UNFILTERED;
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doFilter();
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}
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ARMFilterChooser(const std::vector<const CodeGenInstruction*> &Insts,
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const std::vector<unsigned> &IDs,
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bit_value_t (&ParentFilterBitValues)[BIT_WIDTH],
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ARMFilterChooser &parent) :
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AllInstructions(Insts), Opcodes(IDs), Filters(), Parent(&parent),
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BestIndex(-1) {
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for (unsigned i = 0; i < BIT_WIDTH; ++i)
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FilterBitValues[i] = ParentFilterBitValues[i];
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doFilter();
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}
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// The top level filter chooser has NULL as its parent.
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bool isTopLevel() { return Parent == NULL; }
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// This provides an opportunity for target specific code emission.
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void emitTopHook(raw_ostream &o);
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// Emit the top level typedef and decodeInstruction() function.
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void emitTop(raw_ostream &o, unsigned &Indentation);
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// This provides an opportunity for target specific code emission after
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// emitTop().
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void emitBot(raw_ostream &o, unsigned &Indentation);
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protected:
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// Populates the insn given the uid.
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void insnWithID(insn_t &Insn, unsigned Opcode) const {
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BitsInit &Bits = getBitsField(*AllInstructions[Opcode]->TheDef, "Inst");
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for (unsigned i = 0; i < BIT_WIDTH; ++i)
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Insn[i] = bitFromBits(Bits, i);
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// Set Inst{21} to 1 (wback) when IndexModeBits == IndexModeUpd.
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Record *R = AllInstructions[Opcode]->TheDef;
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if (R->getValue("IndexModeBits") &&
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getByteField(*R, "IndexModeBits") == IndexModeUpd)
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Insn[21] = BIT_TRUE;
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}
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// Returns the record name.
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const std::string &nameWithID(unsigned Opcode) const {
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return AllInstructions[Opcode]->TheDef->getName();
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}
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// Populates the field of the insn given the start position and the number of
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// consecutive bits to scan for.
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//
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// Returns false if there exists any uninitialized bit value in the range.
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// Returns true, otherwise.
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bool fieldFromInsn(uint64_t &Field, insn_t &Insn, unsigned StartBit,
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unsigned NumBits) const;
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/// dumpFilterArray - dumpFilterArray prints out debugging info for the given
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/// filter array as a series of chars.
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void dumpFilterArray(raw_ostream &o, bit_value_t (&filter)[BIT_WIDTH]);
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/// dumpStack - dumpStack traverses the filter chooser chain and calls
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/// dumpFilterArray on each filter chooser up to the top level one.
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void dumpStack(raw_ostream &o, const char *prefix);
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ARMFilter &bestFilter() {
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assert(BestIndex != -1 && "BestIndex not set");
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return Filters[BestIndex];
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}
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// Called from Filter::recurse() when singleton exists. For debug purpose.
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void SingletonExists(unsigned Opc);
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bool PositionFiltered(unsigned i) {
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return ValueSet(FilterBitValues[i]);
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}
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// Calculates the island(s) needed to decode the instruction.
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// This returns a lit of undecoded bits of an instructions, for example,
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// Inst{20} = 1 && Inst{3-0} == 0b1111 represents two islands of yet-to-be
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// decoded bits in order to verify that the instruction matches the Opcode.
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unsigned getIslands(std::vector<unsigned> &StartBits,
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std::vector<unsigned> &EndBits, std::vector<uint64_t> &FieldVals,
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insn_t &Insn);
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// The purpose of this function is for the API client to detect possible
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// Load/Store Coprocessor instructions. If the coprocessor number is of
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// the instruction is either 10 or 11, the decoder should not report the
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// instruction as LDC/LDC2/STC/STC2, but should match against Advanced SIMD or
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// VFP instructions.
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bool LdStCopEncoding1(unsigned Opc) {
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const std::string &Name = nameWithID(Opc);
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if (Name == "LDC_OFFSET" || Name == "LDC_OPTION" ||
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Name == "LDC_POST" || Name == "LDC_PRE" ||
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Name == "LDCL_OFFSET" || Name == "LDCL_OPTION" ||
|
|
Name == "LDCL_POST" || Name == "LDCL_PRE" ||
|
|
Name == "STC_OFFSET" || Name == "STC_OPTION" ||
|
|
Name == "STC_POST" || Name == "STC_PRE" ||
|
|
Name == "STCL_OFFSET" || Name == "STCL_OPTION" ||
|
|
Name == "STCL_POST" || Name == "STCL_PRE")
|
|
return true;
|
|
else
|
|
return false;
|
|
}
|
|
|
|
// Emits code to decode the singleton. Return true if we have matched all the
|
|
// well-known bits.
|
|
bool emitSingletonDecoder(raw_ostream &o, unsigned &Indentation,unsigned Opc);
|
|
|
|
// Emits code to decode the singleton, and then to decode the rest.
|
|
void emitSingletonDecoder(raw_ostream &o, unsigned &Indentation,
|
|
ARMFilter &Best);
|
|
|
|
// Assign a single filter and run with it.
|
|
void runSingleFilter(ARMFilterChooser &owner, unsigned startBit,
|
|
unsigned numBit, bool mixed);
|
|
|
|
// reportRegion is a helper function for filterProcessor to mark a region as
|
|
// eligible for use as a filter region.
|
|
void reportRegion(bitAttr_t RA, unsigned StartBit, unsigned BitIndex,
|
|
bool AllowMixed);
|
|
|
|
// FilterProcessor scans the well-known encoding bits of the instructions and
|
|
// builds up a list of candidate filters. It chooses the best filter and
|
|
// recursively descends down the decoding tree.
|
|
bool filterProcessor(bool AllowMixed, bool Greedy = true);
|
|
|
|
// Decides on the best configuration of filter(s) to use in order to decode
|
|
// the instructions. A conflict of instructions may occur, in which case we
|
|
// dump the conflict set to the standard error.
|
|
void doFilter();
|
|
|
|
// Emits code to decode our share of instructions. Returns true if the
|
|
// emitted code causes a return, which occurs if we know how to decode
|
|
// the instruction at this level or the instruction is not decodeable.
|
|
bool emit(raw_ostream &o, unsigned &Indentation);
|
|
};
|
|
|
|
///////////////////////////
|
|
// //
|
|
// Filter Implmenetation //
|
|
// //
|
|
///////////////////////////
|
|
|
|
ARMFilter::ARMFilter(const ARMFilter &f) :
|
|
Owner(f.Owner), StartBit(f.StartBit), NumBits(f.NumBits), Mixed(f.Mixed),
|
|
FilteredInstructions(f.FilteredInstructions),
|
|
VariableInstructions(f.VariableInstructions),
|
|
FilterChooserMap(f.FilterChooserMap), NumFiltered(f.NumFiltered),
|
|
LastOpcFiltered(f.LastOpcFiltered), NumVariable(f.NumVariable) {
|
|
}
|
|
|
|
ARMFilter::ARMFilter(ARMFilterChooser &owner, unsigned startBit, unsigned numBits,
|
|
bool mixed) : Owner(&owner), StartBit(startBit), NumBits(numBits),
|
|
Mixed(mixed) {
|
|
assert(StartBit + NumBits - 1 < BIT_WIDTH);
|
|
|
|
NumFiltered = 0;
|
|
LastOpcFiltered = 0;
|
|
NumVariable = 0;
|
|
|
|
for (unsigned i = 0, e = Owner->Opcodes.size(); i != e; ++i) {
|
|
insn_t Insn;
|
|
|
|
// Populates the insn given the uid.
|
|
Owner->insnWithID(Insn, Owner->Opcodes[i]);
|
|
|
|
uint64_t Field;
|
|
// Scans the segment for possibly well-specified encoding bits.
|
|
bool ok = Owner->fieldFromInsn(Field, Insn, StartBit, NumBits);
|
|
|
|
if (ok) {
|
|
// The encoding bits are well-known. Lets add the uid of the
|
|
// instruction into the bucket keyed off the constant field value.
|
|
LastOpcFiltered = Owner->Opcodes[i];
|
|
FilteredInstructions[Field].push_back(LastOpcFiltered);
|
|
++NumFiltered;
|
|
} else {
|
|
// Some of the encoding bit(s) are unspecfied. This contributes to
|
|
// one additional member of "Variable" instructions.
|
|
VariableInstructions.push_back(Owner->Opcodes[i]);
|
|
++NumVariable;
|
|
}
|
|
}
|
|
|
|
assert((FilteredInstructions.size() + VariableInstructions.size() > 0)
|
|
&& "Filter returns no instruction categories");
|
|
}
|
|
|
|
ARMFilter::~ARMFilter() {
|
|
std::map<unsigned, ARMFilterChooser*>::iterator filterIterator;
|
|
for (filterIterator = FilterChooserMap.begin();
|
|
filterIterator != FilterChooserMap.end();
|
|
filterIterator++) {
|
|
delete filterIterator->second;
|
|
}
|
|
}
|
|
|
|
// Divides the decoding task into sub tasks and delegates them to the
|
|
// inferior FilterChooser's.
|
|
//
|
|
// A special case arises when there's only one entry in the filtered
|
|
// instructions. In order to unambiguously decode the singleton, we need to
|
|
// match the remaining undecoded encoding bits against the singleton.
|
|
void ARMFilter::recurse() {
|
|
std::map<uint64_t, std::vector<unsigned> >::const_iterator mapIterator;
|
|
|
|
bit_value_t BitValueArray[BIT_WIDTH];
|
|
// Starts by inheriting our parent filter chooser's filter bit values.
|
|
memcpy(BitValueArray, Owner->FilterBitValues, sizeof(BitValueArray));
|
|
|
|
unsigned bitIndex;
|
|
|
|
if (VariableInstructions.size()) {
|
|
// Conservatively marks each segment position as BIT_UNSET.
|
|
for (bitIndex = 0; bitIndex < NumBits; bitIndex++)
|
|
BitValueArray[StartBit + bitIndex] = BIT_UNSET;
|
|
|
|
// Delegates to an inferior filter chooser for further processing on this
|
|
// group of instructions whose segment values are variable.
|
|
FilterChooserMap.insert(std::pair<unsigned, ARMFilterChooser*>(
|
|
(unsigned)-1,
|
|
new ARMFilterChooser(Owner->AllInstructions,
|
|
VariableInstructions,
|
|
BitValueArray,
|
|
*Owner)
|
|
));
|
|
}
|
|
|
|
// No need to recurse for a singleton filtered instruction.
|
|
// See also Filter::emit().
|
|
if (getNumFiltered() == 1) {
|
|
//Owner->SingletonExists(LastOpcFiltered);
|
|
assert(FilterChooserMap.size() == 1);
|
|
return;
|
|
}
|
|
|
|
// Otherwise, create sub choosers.
|
|
for (mapIterator = FilteredInstructions.begin();
|
|
mapIterator != FilteredInstructions.end();
|
|
mapIterator++) {
|
|
|
|
// Marks all the segment positions with either BIT_TRUE or BIT_FALSE.
|
|
for (bitIndex = 0; bitIndex < NumBits; bitIndex++) {
|
|
if (mapIterator->first & (1ULL << bitIndex))
|
|
BitValueArray[StartBit + bitIndex] = BIT_TRUE;
|
|
else
|
|
BitValueArray[StartBit + bitIndex] = BIT_FALSE;
|
|
}
|
|
|
|
// Delegates to an inferior filter chooser for further processing on this
|
|
// category of instructions.
|
|
FilterChooserMap.insert(std::pair<unsigned, ARMFilterChooser*>(
|
|
mapIterator->first,
|
|
new ARMFilterChooser(Owner->AllInstructions,
|
|
mapIterator->second,
|
|
BitValueArray,
|
|
*Owner)
|
|
));
|
|
}
|
|
}
|
|
|
|
// Emit code to decode instructions given a segment or segments of bits.
|
|
void ARMFilter::emit(raw_ostream &o, unsigned &Indentation) {
|
|
o.indent(Indentation) << "// Check Inst{";
|
|
|
|
if (NumBits > 1)
|
|
o << (StartBit + NumBits - 1) << '-';
|
|
|
|
o << StartBit << "} ...\n";
|
|
|
|
o.indent(Indentation) << "switch (fieldFromInstruction(insn, "
|
|
<< StartBit << ", " << NumBits << ")) {\n";
|
|
|
|
std::map<unsigned, ARMFilterChooser*>::iterator filterIterator;
|
|
|
|
bool DefaultCase = false;
|
|
for (filterIterator = FilterChooserMap.begin();
|
|
filterIterator != FilterChooserMap.end();
|
|
filterIterator++) {
|
|
|
|
// Field value -1 implies a non-empty set of variable instructions.
|
|
// See also recurse().
|
|
if (filterIterator->first == (unsigned)-1) {
|
|
DefaultCase = true;
|
|
|
|
o.indent(Indentation) << "default:\n";
|
|
o.indent(Indentation) << " break; // fallthrough\n";
|
|
|
|
// Closing curly brace for the switch statement.
|
|
// This is unconventional because we want the default processing to be
|
|
// performed for the fallthrough cases as well, i.e., when the "cases"
|
|
// did not prove a decoded instruction.
|
|
o.indent(Indentation) << "}\n";
|
|
|
|
} else
|
|
o.indent(Indentation) << "case " << filterIterator->first << ":\n";
|
|
|
|
// We arrive at a category of instructions with the same segment value.
|
|
// Now delegate to the sub filter chooser for further decodings.
|
|
// The case may fallthrough, which happens if the remaining well-known
|
|
// encoding bits do not match exactly.
|
|
if (!DefaultCase) { ++Indentation; ++Indentation; }
|
|
|
|
bool finished = filterIterator->second->emit(o, Indentation);
|
|
// For top level default case, there's no need for a break statement.
|
|
if (Owner->isTopLevel() && DefaultCase)
|
|
break;
|
|
if (!finished)
|
|
o.indent(Indentation) << "break;\n";
|
|
|
|
if (!DefaultCase) { --Indentation; --Indentation; }
|
|
}
|
|
|
|
// If there is no default case, we still need to supply a closing brace.
|
|
if (!DefaultCase) {
|
|
// Closing curly brace for the switch statement.
|
|
o.indent(Indentation) << "}\n";
|
|
}
|
|
}
|
|
|
|
// Returns the number of fanout produced by the filter. More fanout implies
|
|
// the filter distinguishes more categories of instructions.
|
|
unsigned ARMFilter::usefulness() const {
|
|
if (VariableInstructions.size())
|
|
return FilteredInstructions.size();
|
|
else
|
|
return FilteredInstructions.size() + 1;
|
|
}
|
|
|
|
//////////////////////////////////
|
|
// //
|
|
// Filterchooser Implementation //
|
|
// //
|
|
//////////////////////////////////
|
|
|
|
// Define the symbol here.
|
|
TARGET_NAME_t ARMFilterChooser::TargetName;
|
|
|
|
// This provides an opportunity for target specific code emission.
|
|
void ARMFilterChooser::emitTopHook(raw_ostream &o) {
|
|
if (TargetName == TARGET_ARM) {
|
|
// Emit code that references the ARMFormat data type.
|
|
o << "static const ARMFormat ARMFormats[] = {\n";
|
|
for (unsigned i = 0, e = AllInstructions.size(); i != e; ++i) {
|
|
const Record &Def = *(AllInstructions[i]->TheDef);
|
|
const std::string &Name = Def.getName();
|
|
if (Def.isSubClassOf("InstARM") || Def.isSubClassOf("InstThumb"))
|
|
o.indent(2) <<
|
|
stringForARMFormat((ARMFormat)getByteField(Def, "Form"));
|
|
else
|
|
o << " ARM_FORMAT_NA";
|
|
|
|
o << ",\t// Inst #" << i << " = " << Name << '\n';
|
|
}
|
|
o << " ARM_FORMAT_NA\t// Unreachable.\n";
|
|
o << "};\n\n";
|
|
}
|
|
}
|
|
|
|
// Emit the top level typedef and decodeInstruction() function.
|
|
void ARMFilterChooser::emitTop(raw_ostream &o, unsigned &Indentation) {
|
|
// Run the target specific emit hook.
|
|
emitTopHook(o);
|
|
|
|
switch (BIT_WIDTH) {
|
|
case 8:
|
|
o.indent(Indentation) << "typedef uint8_t field_t;\n";
|
|
break;
|
|
case 16:
|
|
o.indent(Indentation) << "typedef uint16_t field_t;\n";
|
|
break;
|
|
case 32:
|
|
o.indent(Indentation) << "typedef uint32_t field_t;\n";
|
|
break;
|
|
case 64:
|
|
o.indent(Indentation) << "typedef uint64_t field_t;\n";
|
|
break;
|
|
default:
|
|
assert(0 && "Unexpected instruction size!");
|
|
}
|
|
|
|
o << '\n';
|
|
|
|
o.indent(Indentation) << "static field_t " <<
|
|
"fieldFromInstruction(field_t insn, unsigned startBit, unsigned numBits)\n";
|
|
|
|
o.indent(Indentation) << "{\n";
|
|
|
|
++Indentation; ++Indentation;
|
|
o.indent(Indentation) << "assert(startBit + numBits <= " << BIT_WIDTH
|
|
<< " && \"Instruction field out of bounds!\");\n";
|
|
o << '\n';
|
|
o.indent(Indentation) << "field_t fieldMask;\n";
|
|
o << '\n';
|
|
o.indent(Indentation) << "if (numBits == " << BIT_WIDTH << ")\n";
|
|
|
|
++Indentation; ++Indentation;
|
|
o.indent(Indentation) << "fieldMask = (field_t)-1;\n";
|
|
--Indentation; --Indentation;
|
|
|
|
o.indent(Indentation) << "else\n";
|
|
|
|
++Indentation; ++Indentation;
|
|
o.indent(Indentation) << "fieldMask = ((1 << numBits) - 1) << startBit;\n";
|
|
--Indentation; --Indentation;
|
|
|
|
o << '\n';
|
|
o.indent(Indentation) << "return (insn & fieldMask) >> startBit;\n";
|
|
--Indentation; --Indentation;
|
|
|
|
o.indent(Indentation) << "}\n";
|
|
|
|
o << '\n';
|
|
|
|
o.indent(Indentation) <<"static uint16_t decodeInstruction(field_t insn) {\n";
|
|
|
|
++Indentation; ++Indentation;
|
|
// Emits code to decode the instructions.
|
|
emit(o, Indentation);
|
|
|
|
o << '\n';
|
|
o.indent(Indentation) << "return 0;\n";
|
|
--Indentation; --Indentation;
|
|
|
|
o.indent(Indentation) << "}\n";
|
|
|
|
o << '\n';
|
|
}
|
|
|
|
// This provides an opportunity for target specific code emission after
|
|
// emitTop().
|
|
void ARMFilterChooser::emitBot(raw_ostream &o, unsigned &Indentation) {
|
|
if (TargetName != TARGET_THUMB) return;
|
|
|
|
// Emit code that decodes the Thumb ISA.
|
|
o.indent(Indentation)
|
|
<< "static uint16_t decodeThumbInstruction(field_t insn) {\n";
|
|
|
|
++Indentation; ++Indentation;
|
|
|
|
// Emits code to decode the instructions.
|
|
emit(o, Indentation);
|
|
|
|
o << '\n';
|
|
o.indent(Indentation) << "return 0;\n";
|
|
|
|
--Indentation; --Indentation;
|
|
|
|
o.indent(Indentation) << "}\n";
|
|
}
|
|
|
|
// Populates the field of the insn given the start position and the number of
|
|
// consecutive bits to scan for.
|
|
//
|
|
// Returns false if and on the first uninitialized bit value encountered.
|
|
// Returns true, otherwise.
|
|
bool ARMFilterChooser::fieldFromInsn(uint64_t &Field, insn_t &Insn,
|
|
unsigned StartBit, unsigned NumBits) const {
|
|
Field = 0;
|
|
|
|
for (unsigned i = 0; i < NumBits; ++i) {
|
|
if (Insn[StartBit + i] == BIT_UNSET)
|
|
return false;
|
|
|
|
if (Insn[StartBit + i] == BIT_TRUE)
|
|
Field = Field | (1ULL << i);
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/// dumpFilterArray - dumpFilterArray prints out debugging info for the given
|
|
/// filter array as a series of chars.
|
|
void ARMFilterChooser::dumpFilterArray(raw_ostream &o,
|
|
bit_value_t (&filter)[BIT_WIDTH]) {
|
|
unsigned bitIndex;
|
|
|
|
for (bitIndex = BIT_WIDTH; bitIndex > 0; bitIndex--) {
|
|
switch (filter[bitIndex - 1]) {
|
|
case BIT_UNFILTERED:
|
|
o << ".";
|
|
break;
|
|
case BIT_UNSET:
|
|
o << "_";
|
|
break;
|
|
case BIT_TRUE:
|
|
o << "1";
|
|
break;
|
|
case BIT_FALSE:
|
|
o << "0";
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/// dumpStack - dumpStack traverses the filter chooser chain and calls
|
|
/// dumpFilterArray on each filter chooser up to the top level one.
|
|
void ARMFilterChooser::dumpStack(raw_ostream &o, const char *prefix) {
|
|
ARMFilterChooser *current = this;
|
|
|
|
while (current) {
|
|
o << prefix;
|
|
dumpFilterArray(o, current->FilterBitValues);
|
|
o << '\n';
|
|
current = current->Parent;
|
|
}
|
|
}
|
|
|
|
// Called from Filter::recurse() when singleton exists. For debug purpose.
|
|
void ARMFilterChooser::SingletonExists(unsigned Opc) {
|
|
insn_t Insn0;
|
|
insnWithID(Insn0, Opc);
|
|
|
|
errs() << "Singleton exists: " << nameWithID(Opc)
|
|
<< " with its decoding dominating ";
|
|
for (unsigned i = 0; i < Opcodes.size(); ++i) {
|
|
if (Opcodes[i] == Opc) continue;
|
|
errs() << nameWithID(Opcodes[i]) << ' ';
|
|
}
|
|
errs() << '\n';
|
|
|
|
dumpStack(errs(), "\t\t");
|
|
for (unsigned i = 0; i < Opcodes.size(); i++) {
|
|
const std::string &Name = nameWithID(Opcodes[i]);
|
|
|
|
errs() << '\t' << Name << " ";
|
|
dumpBits(errs(),
|
|
getBitsField(*AllInstructions[Opcodes[i]]->TheDef, "Inst"));
|
|
errs() << '\n';
|
|
}
|
|
}
|
|
|
|
// Calculates the island(s) needed to decode the instruction.
|
|
// This returns a list of undecoded bits of an instructions, for example,
|
|
// Inst{20} = 1 && Inst{3-0} == 0b1111 represents two islands of yet-to-be
|
|
// decoded bits in order to verify that the instruction matches the Opcode.
|
|
unsigned ARMFilterChooser::getIslands(std::vector<unsigned> &StartBits,
|
|
std::vector<unsigned> &EndBits, std::vector<uint64_t> &FieldVals,
|
|
insn_t &Insn) {
|
|
unsigned Num, BitNo;
|
|
Num = BitNo = 0;
|
|
|
|
uint64_t FieldVal = 0;
|
|
|
|
// 0: Init
|
|
// 1: Water (the bit value does not affect decoding)
|
|
// 2: Island (well-known bit value needed for decoding)
|
|
int State = 0;
|
|
int Val = -1;
|
|
|
|
for (unsigned i = 0; i < BIT_WIDTH; ++i) {
|
|
Val = Value(Insn[i]);
|
|
bool Filtered = PositionFiltered(i);
|
|
switch (State) {
|
|
default:
|
|
assert(0 && "Unreachable code!");
|
|
break;
|
|
case 0:
|
|
case 1:
|
|
if (Filtered || Val == -1)
|
|
State = 1; // Still in Water
|
|
else {
|
|
State = 2; // Into the Island
|
|
BitNo = 0;
|
|
StartBits.push_back(i);
|
|
FieldVal = Val;
|
|
}
|
|
break;
|
|
case 2:
|
|
if (Filtered || Val == -1) {
|
|
State = 1; // Into the Water
|
|
EndBits.push_back(i - 1);
|
|
FieldVals.push_back(FieldVal);
|
|
++Num;
|
|
} else {
|
|
State = 2; // Still in Island
|
|
++BitNo;
|
|
FieldVal = FieldVal | Val << BitNo;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
// If we are still in Island after the loop, do some housekeeping.
|
|
if (State == 2) {
|
|
EndBits.push_back(BIT_WIDTH - 1);
|
|
FieldVals.push_back(FieldVal);
|
|
++Num;
|
|
}
|
|
|
|
assert(StartBits.size() == Num && EndBits.size() == Num &&
|
|
FieldVals.size() == Num);
|
|
return Num;
|
|
}
|
|
|
|
// Emits code to decode the singleton. Return true if we have matched all the
|
|
// well-known bits.
|
|
bool ARMFilterChooser::emitSingletonDecoder(raw_ostream &o, unsigned &Indentation,
|
|
unsigned Opc) {
|
|
std::vector<unsigned> StartBits;
|
|
std::vector<unsigned> EndBits;
|
|
std::vector<uint64_t> FieldVals;
|
|
insn_t Insn;
|
|
insnWithID(Insn, Opc);
|
|
|
|
// This provides a good opportunity to check for possible Ld/St Coprocessor
|
|
// Opcode and escapes if the coproc # is either 10 or 11. It is a NEON/VFP
|
|
// instruction is disguise.
|
|
if (TargetName == TARGET_ARM && LdStCopEncoding1(Opc)) {
|
|
o.indent(Indentation);
|
|
// A8.6.51 & A8.6.188
|
|
// If coproc = 0b101?, i.e, slice(insn, 11, 8) = 10 or 11, escape.
|
|
o << "if (fieldFromInstruction(insn, 9, 3) == 5) break; // fallthrough\n";
|
|
}
|
|
|
|
// Look for islands of undecoded bits of the singleton.
|
|
getIslands(StartBits, EndBits, FieldVals, Insn);
|
|
|
|
unsigned Size = StartBits.size();
|
|
unsigned I, NumBits;
|
|
|
|
// If we have matched all the well-known bits, just issue a return.
|
|
if (Size == 0) {
|
|
o.indent(Indentation) << "return " << Opc << "; // " << nameWithID(Opc)
|
|
<< '\n';
|
|
return true;
|
|
}
|
|
|
|
// Otherwise, there are more decodings to be done!
|
|
|
|
// Emit code to match the island(s) for the singleton.
|
|
o.indent(Indentation) << "// Check ";
|
|
|
|
for (I = Size; I != 0; --I) {
|
|
o << "Inst{" << EndBits[I-1] << '-' << StartBits[I-1] << "} ";
|
|
if (I > 1)
|
|
o << "&& ";
|
|
else
|
|
o << "for singleton decoding...\n";
|
|
}
|
|
|
|
o.indent(Indentation) << "if (";
|
|
|
|
for (I = Size; I != 0; --I) {
|
|
NumBits = EndBits[I-1] - StartBits[I-1] + 1;
|
|
o << "fieldFromInstruction(insn, " << StartBits[I-1] << ", " << NumBits
|
|
<< ") == " << FieldVals[I-1];
|
|
if (I > 1)
|
|
o << " && ";
|
|
else
|
|
o << ")\n";
|
|
}
|
|
|
|
o.indent(Indentation) << " return " << Opc << "; // " << nameWithID(Opc)
|
|
<< '\n';
|
|
|
|
return false;
|
|
}
|
|
|
|
// Emits code to decode the singleton, and then to decode the rest.
|
|
void ARMFilterChooser::emitSingletonDecoder(raw_ostream &o,
|
|
unsigned &Indentation,
|
|
ARMFilter &Best) {
|
|
|
|
unsigned Opc = Best.getSingletonOpc();
|
|
|
|
emitSingletonDecoder(o, Indentation, Opc);
|
|
|
|
// Emit code for the rest.
|
|
o.indent(Indentation) << "else\n";
|
|
|
|
Indentation += 2;
|
|
Best.getVariableFC().emit(o, Indentation);
|
|
Indentation -= 2;
|
|
}
|
|
|
|
// Assign a single filter and run with it. Top level API client can initialize
|
|
// with a single filter to start the filtering process.
|
|
void ARMFilterChooser::runSingleFilter(ARMFilterChooser &owner,
|
|
unsigned startBit,
|
|
unsigned numBit, bool mixed) {
|
|
Filters.clear();
|
|
ARMFilter F(*this, startBit, numBit, true);
|
|
Filters.push_back(F);
|
|
BestIndex = 0; // Sole Filter instance to choose from.
|
|
bestFilter().recurse();
|
|
}
|
|
|
|
// reportRegion is a helper function for filterProcessor to mark a region as
|
|
// eligible for use as a filter region.
|
|
void ARMFilterChooser::reportRegion(bitAttr_t RA, unsigned StartBit,
|
|
unsigned BitIndex, bool AllowMixed) {
|
|
if (RA == ATTR_MIXED && AllowMixed)
|
|
Filters.push_back(ARMFilter(*this, StartBit, BitIndex - StartBit, true));
|
|
else if (RA == ATTR_ALL_SET && !AllowMixed)
|
|
Filters.push_back(ARMFilter(*this, StartBit, BitIndex - StartBit, false));
|
|
}
|
|
|
|
// FilterProcessor scans the well-known encoding bits of the instructions and
|
|
// builds up a list of candidate filters. It chooses the best filter and
|
|
// recursively descends down the decoding tree.
|
|
bool ARMFilterChooser::filterProcessor(bool AllowMixed, bool Greedy) {
|
|
Filters.clear();
|
|
BestIndex = -1;
|
|
unsigned numInstructions = Opcodes.size();
|
|
|
|
assert(numInstructions && "Filter created with no instructions");
|
|
|
|
// No further filtering is necessary.
|
|
if (numInstructions == 1)
|
|
return true;
|
|
|
|
// Heuristics. See also doFilter()'s "Heuristics" comment when num of
|
|
// instructions is 3.
|
|
if (AllowMixed && !Greedy) {
|
|
assert(numInstructions == 3);
|
|
|
|
for (unsigned i = 0; i < Opcodes.size(); ++i) {
|
|
std::vector<unsigned> StartBits;
|
|
std::vector<unsigned> EndBits;
|
|
std::vector<uint64_t> FieldVals;
|
|
insn_t Insn;
|
|
|
|
insnWithID(Insn, Opcodes[i]);
|
|
|
|
// Look for islands of undecoded bits of any instruction.
|
|
if (getIslands(StartBits, EndBits, FieldVals, Insn) > 0) {
|
|
// Found an instruction with island(s). Now just assign a filter.
|
|
runSingleFilter(*this, StartBits[0], EndBits[0] - StartBits[0] + 1,
|
|
true);
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
unsigned BitIndex, InsnIndex;
|
|
|
|
// We maintain BIT_WIDTH copies of the bitAttrs automaton.
|
|
// The automaton consumes the corresponding bit from each
|
|
// instruction.
|
|
//
|
|
// Input symbols: 0, 1, and _ (unset).
|
|
// States: NONE, FILTERED, ALL_SET, ALL_UNSET, and MIXED.
|
|
// Initial state: NONE.
|
|
//
|
|
// (NONE) ------- [01] -> (ALL_SET)
|
|
// (NONE) ------- _ ----> (ALL_UNSET)
|
|
// (ALL_SET) ---- [01] -> (ALL_SET)
|
|
// (ALL_SET) ---- _ ----> (MIXED)
|
|
// (ALL_UNSET) -- [01] -> (MIXED)
|
|
// (ALL_UNSET) -- _ ----> (ALL_UNSET)
|
|
// (MIXED) ------ . ----> (MIXED)
|
|
// (FILTERED)---- . ----> (FILTERED)
|
|
|
|
bitAttr_t bitAttrs[BIT_WIDTH];
|
|
|
|
// FILTERED bit positions provide no entropy and are not worthy of pursuing.
|
|
// Filter::recurse() set either BIT_TRUE or BIT_FALSE for each position.
|
|
for (BitIndex = 0; BitIndex < BIT_WIDTH; ++BitIndex)
|
|
if (FilterBitValues[BitIndex] == BIT_TRUE ||
|
|
FilterBitValues[BitIndex] == BIT_FALSE)
|
|
bitAttrs[BitIndex] = ATTR_FILTERED;
|
|
else
|
|
bitAttrs[BitIndex] = ATTR_NONE;
|
|
|
|
for (InsnIndex = 0; InsnIndex < numInstructions; ++InsnIndex) {
|
|
insn_t insn;
|
|
|
|
insnWithID(insn, Opcodes[InsnIndex]);
|
|
|
|
for (BitIndex = 0; BitIndex < BIT_WIDTH; ++BitIndex) {
|
|
switch (bitAttrs[BitIndex]) {
|
|
case ATTR_NONE:
|
|
if (insn[BitIndex] == BIT_UNSET)
|
|
bitAttrs[BitIndex] = ATTR_ALL_UNSET;
|
|
else
|
|
bitAttrs[BitIndex] = ATTR_ALL_SET;
|
|
break;
|
|
case ATTR_ALL_SET:
|
|
if (insn[BitIndex] == BIT_UNSET)
|
|
bitAttrs[BitIndex] = ATTR_MIXED;
|
|
break;
|
|
case ATTR_ALL_UNSET:
|
|
if (insn[BitIndex] != BIT_UNSET)
|
|
bitAttrs[BitIndex] = ATTR_MIXED;
|
|
break;
|
|
case ATTR_MIXED:
|
|
case ATTR_FILTERED:
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// The regionAttr automaton consumes the bitAttrs automatons' state,
|
|
// lowest-to-highest.
|
|
//
|
|
// Input symbols: F(iltered), (all_)S(et), (all_)U(nset), M(ixed)
|
|
// States: NONE, ALL_SET, MIXED
|
|
// Initial state: NONE
|
|
//
|
|
// (NONE) ----- F --> (NONE)
|
|
// (NONE) ----- S --> (ALL_SET) ; and set region start
|
|
// (NONE) ----- U --> (NONE)
|
|
// (NONE) ----- M --> (MIXED) ; and set region start
|
|
// (ALL_SET) -- F --> (NONE) ; and report an ALL_SET region
|
|
// (ALL_SET) -- S --> (ALL_SET)
|
|
// (ALL_SET) -- U --> (NONE) ; and report an ALL_SET region
|
|
// (ALL_SET) -- M --> (MIXED) ; and report an ALL_SET region
|
|
// (MIXED) ---- F --> (NONE) ; and report a MIXED region
|
|
// (MIXED) ---- S --> (ALL_SET) ; and report a MIXED region
|
|
// (MIXED) ---- U --> (NONE) ; and report a MIXED region
|
|
// (MIXED) ---- M --> (MIXED)
|
|
|
|
bitAttr_t RA = ATTR_NONE;
|
|
unsigned StartBit = 0;
|
|
|
|
for (BitIndex = 0; BitIndex < BIT_WIDTH; BitIndex++) {
|
|
bitAttr_t bitAttr = bitAttrs[BitIndex];
|
|
|
|
assert(bitAttr != ATTR_NONE && "Bit without attributes");
|
|
|
|
switch (RA) {
|
|
case ATTR_NONE:
|
|
switch (bitAttr) {
|
|
case ATTR_FILTERED:
|
|
break;
|
|
case ATTR_ALL_SET:
|
|
StartBit = BitIndex;
|
|
RA = ATTR_ALL_SET;
|
|
break;
|
|
case ATTR_ALL_UNSET:
|
|
break;
|
|
case ATTR_MIXED:
|
|
StartBit = BitIndex;
|
|
RA = ATTR_MIXED;
|
|
break;
|
|
default:
|
|
assert(0 && "Unexpected bitAttr!");
|
|
}
|
|
break;
|
|
case ATTR_ALL_SET:
|
|
switch (bitAttr) {
|
|
case ATTR_FILTERED:
|
|
reportRegion(RA, StartBit, BitIndex, AllowMixed);
|
|
RA = ATTR_NONE;
|
|
break;
|
|
case ATTR_ALL_SET:
|
|
break;
|
|
case ATTR_ALL_UNSET:
|
|
reportRegion(RA, StartBit, BitIndex, AllowMixed);
|
|
RA = ATTR_NONE;
|
|
break;
|
|
case ATTR_MIXED:
|
|
reportRegion(RA, StartBit, BitIndex, AllowMixed);
|
|
StartBit = BitIndex;
|
|
RA = ATTR_MIXED;
|
|
break;
|
|
default:
|
|
assert(0 && "Unexpected bitAttr!");
|
|
}
|
|
break;
|
|
case ATTR_MIXED:
|
|
switch (bitAttr) {
|
|
case ATTR_FILTERED:
|
|
reportRegion(RA, StartBit, BitIndex, AllowMixed);
|
|
StartBit = BitIndex;
|
|
RA = ATTR_NONE;
|
|
break;
|
|
case ATTR_ALL_SET:
|
|
reportRegion(RA, StartBit, BitIndex, AllowMixed);
|
|
StartBit = BitIndex;
|
|
RA = ATTR_ALL_SET;
|
|
break;
|
|
case ATTR_ALL_UNSET:
|
|
reportRegion(RA, StartBit, BitIndex, AllowMixed);
|
|
RA = ATTR_NONE;
|
|
break;
|
|
case ATTR_MIXED:
|
|
break;
|
|
default:
|
|
assert(0 && "Unexpected bitAttr!");
|
|
}
|
|
break;
|
|
case ATTR_ALL_UNSET:
|
|
assert(0 && "regionAttr state machine has no ATTR_UNSET state");
|
|
case ATTR_FILTERED:
|
|
assert(0 && "regionAttr state machine has no ATTR_FILTERED state");
|
|
}
|
|
}
|
|
|
|
// At the end, if we're still in ALL_SET or MIXED states, report a region
|
|
switch (RA) {
|
|
case ATTR_NONE:
|
|
break;
|
|
case ATTR_FILTERED:
|
|
break;
|
|
case ATTR_ALL_SET:
|
|
reportRegion(RA, StartBit, BitIndex, AllowMixed);
|
|
break;
|
|
case ATTR_ALL_UNSET:
|
|
break;
|
|
case ATTR_MIXED:
|
|
reportRegion(RA, StartBit, BitIndex, AllowMixed);
|
|
break;
|
|
}
|
|
|
|
// We have finished with the filter processings. Now it's time to choose
|
|
// the best performing filter.
|
|
BestIndex = 0;
|
|
bool AllUseless = true;
|
|
unsigned BestScore = 0;
|
|
|
|
for (unsigned i = 0, e = Filters.size(); i != e; ++i) {
|
|
unsigned Usefulness = Filters[i].usefulness();
|
|
|
|
if (Usefulness)
|
|
AllUseless = false;
|
|
|
|
if (Usefulness > BestScore) {
|
|
BestIndex = i;
|
|
BestScore = Usefulness;
|
|
}
|
|
}
|
|
|
|
if (!AllUseless)
|
|
bestFilter().recurse();
|
|
|
|
return !AllUseless;
|
|
} // end of FilterChooser::filterProcessor(bool)
|
|
|
|
// Decides on the best configuration of filter(s) to use in order to decode
|
|
// the instructions. A conflict of instructions may occur, in which case we
|
|
// dump the conflict set to the standard error.
|
|
void ARMFilterChooser::doFilter() {
|
|
unsigned Num = Opcodes.size();
|
|
assert(Num && "FilterChooser created with no instructions");
|
|
|
|
// Heuristics: Use Inst{31-28} as the top level filter for ARM ISA.
|
|
if (TargetName == TARGET_ARM && Parent == NULL) {
|
|
runSingleFilter(*this, 28, 4, false);
|
|
return;
|
|
}
|
|
|
|
// Try regions of consecutive known bit values first.
|
|
if (filterProcessor(false))
|
|
return;
|
|
|
|
// Then regions of mixed bits (both known and unitialized bit values allowed).
|
|
if (filterProcessor(true))
|
|
return;
|
|
|
|
// Heuristics to cope with conflict set {t2CMPrs, t2SUBSrr, t2SUBSrs} where
|
|
// no single instruction for the maximum ATTR_MIXED region Inst{14-4} has a
|
|
// well-known encoding pattern. In such case, we backtrack and scan for the
|
|
// the very first consecutive ATTR_ALL_SET region and assign a filter to it.
|
|
if (Num == 3 && filterProcessor(true, false))
|
|
return;
|
|
|
|
// If we come to here, the instruction decoding has failed.
|
|
// Set the BestIndex to -1 to indicate so.
|
|
BestIndex = -1;
|
|
}
|
|
|
|
// Emits code to decode our share of instructions. Returns true if the
|
|
// emitted code causes a return, which occurs if we know how to decode
|
|
// the instruction at this level or the instruction is not decodeable.
|
|
bool ARMFilterChooser::emit(raw_ostream &o, unsigned &Indentation) {
|
|
if (Opcodes.size() == 1)
|
|
// There is only one instruction in the set, which is great!
|
|
// Call emitSingletonDecoder() to see whether there are any remaining
|
|
// encodings bits.
|
|
return emitSingletonDecoder(o, Indentation, Opcodes[0]);
|
|
|
|
// Choose the best filter to do the decodings!
|
|
if (BestIndex != -1) {
|
|
ARMFilter &Best = bestFilter();
|
|
if (Best.getNumFiltered() == 1)
|
|
emitSingletonDecoder(o, Indentation, Best);
|
|
else
|
|
bestFilter().emit(o, Indentation);
|
|
return false;
|
|
}
|
|
|
|
// If we reach here, there is a conflict in decoding. Let's resolve the known
|
|
// conflicts!
|
|
if ((TargetName == TARGET_ARM || TargetName == TARGET_THUMB) &&
|
|
Opcodes.size() == 2) {
|
|
// Resolve the known conflict sets:
|
|
//
|
|
// 1. source registers are identical => VMOVDneon; otherwise => VORRd
|
|
// 2. source registers are identical => VMOVQ; otherwise => VORRq
|
|
// 3. LDR, LDRcp => return LDR for now.
|
|
// FIXME: How can we distinguish between LDR and LDRcp? Do we need to?
|
|
// 4. tLDMIA, tLDMIA_UPD => Rn = Inst{10-8}, reglist = Inst{7-0},
|
|
// wback = registers<Rn> = 0
|
|
// NOTE: (tLDM, tLDM_UPD) resolution must come before Advanced SIMD
|
|
// addressing mode resolution!!!
|
|
// 5. VLD[234]LN*/VST[234]LN* vs. VLD[234]LN*_UPD/VST[234]LN*_UPD conflicts
|
|
// are resolved returning the non-UPD versions of the instructions if the
|
|
// Rm field, i.e., Inst{3-0} is 0b1111. This is specified in A7.7.1
|
|
// Advanced SIMD addressing mode.
|
|
const std::string &name1 = nameWithID(Opcodes[0]);
|
|
const std::string &name2 = nameWithID(Opcodes[1]);
|
|
if ((name1 == "VMOVDneon" && name2 == "VORRd") ||
|
|
(name1 == "VMOVQ" && name2 == "VORRq")) {
|
|
// Inserting the opening curly brace for this case block.
|
|
--Indentation; --Indentation;
|
|
o.indent(Indentation) << "{\n";
|
|
++Indentation; ++Indentation;
|
|
|
|
o.indent(Indentation)
|
|
<< "field_t N = fieldFromInstruction(insn, 7, 1), "
|
|
<< "M = fieldFromInstruction(insn, 5, 1);\n";
|
|
o.indent(Indentation)
|
|
<< "field_t Vn = fieldFromInstruction(insn, 16, 4), "
|
|
<< "Vm = fieldFromInstruction(insn, 0, 4);\n";
|
|
o.indent(Indentation)
|
|
<< "return (N == M && Vn == Vm) ? "
|
|
<< Opcodes[0] << " /* " << name1 << " */ : "
|
|
<< Opcodes[1] << " /* " << name2 << " */ ;\n";
|
|
|
|
// Inserting the closing curly brace for this case block.
|
|
--Indentation; --Indentation;
|
|
o.indent(Indentation) << "}\n";
|
|
++Indentation; ++Indentation;
|
|
|
|
return true;
|
|
}
|
|
if (name1 == "LDR" && name2 == "LDRcp") {
|
|
o.indent(Indentation)
|
|
<< "return " << Opcodes[0]
|
|
<< "; // Returning LDR for {LDR, LDRcp}\n";
|
|
return true;
|
|
}
|
|
if (name1 == "tLDMIA" && name2 == "tLDMIA_UPD") {
|
|
// Inserting the opening curly brace for this case block.
|
|
--Indentation; --Indentation;
|
|
o.indent(Indentation) << "{\n";
|
|
++Indentation; ++Indentation;
|
|
|
|
o.indent(Indentation)
|
|
<< "unsigned Rn = fieldFromInstruction(insn, 8, 3), "
|
|
<< "list = fieldFromInstruction(insn, 0, 8);\n";
|
|
o.indent(Indentation)
|
|
<< "return ((list >> Rn) & 1) == 0 ? "
|
|
<< Opcodes[1] << " /* " << name2 << " */ : "
|
|
<< Opcodes[0] << " /* " << name1 << " */ ;\n";
|
|
|
|
// Inserting the closing curly brace for this case block.
|
|
--Indentation; --Indentation;
|
|
o.indent(Indentation) << "}\n";
|
|
++Indentation; ++Indentation;
|
|
|
|
return true;
|
|
}
|
|
if (sameStringExceptSuffix(name1, name2, "_UPD")) {
|
|
o.indent(Indentation)
|
|
<< "return fieldFromInstruction(insn, 0, 4) == 15 ? " << Opcodes[0]
|
|
<< " /* " << name1 << " */ : " << Opcodes[1] << "/* " << name2
|
|
<< " */ ; // Advanced SIMD addressing mode\n";
|
|
return true;
|
|
}
|
|
|
|
// Otherwise, it does not belong to the known conflict sets.
|
|
}
|
|
|
|
// We don't know how to decode these instructions! Return 0 and dump the
|
|
// conflict set!
|
|
o.indent(Indentation) << "return 0;" << " // Conflict set: ";
|
|
for (int i = 0, N = Opcodes.size(); i < N; ++i) {
|
|
o << nameWithID(Opcodes[i]);
|
|
if (i < (N - 1))
|
|
o << ", ";
|
|
else
|
|
o << '\n';
|
|
}
|
|
|
|
// Print out useful conflict information for postmortem analysis.
|
|
errs() << "Decoding Conflict:\n";
|
|
|
|
dumpStack(errs(), "\t\t");
|
|
|
|
for (unsigned i = 0; i < Opcodes.size(); i++) {
|
|
const std::string &Name = nameWithID(Opcodes[i]);
|
|
|
|
errs() << '\t' << Name << " ";
|
|
dumpBits(errs(),
|
|
getBitsField(*AllInstructions[Opcodes[i]]->TheDef, "Inst"));
|
|
errs() << '\n';
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
////////////////////////////////////////////
|
|
// //
|
|
// ARMDEBackend //
|
|
// (Helper class for ARMDecoderEmitter) //
|
|
// //
|
|
////////////////////////////////////////////
|
|
|
|
class ARMDecoderEmitter::ARMDEBackend {
|
|
public:
|
|
ARMDEBackend(ARMDecoderEmitter &frontend, RecordKeeper &Records) :
|
|
NumberedInstructions(),
|
|
Opcodes(),
|
|
Frontend(frontend),
|
|
Target(Records),
|
|
FC(NULL)
|
|
{
|
|
if (Target.getName() == "ARM")
|
|
TargetName = TARGET_ARM;
|
|
else {
|
|
errs() << "Target name " << Target.getName() << " not recognized\n";
|
|
assert(0 && "Unknown target");
|
|
}
|
|
|
|
// Populate the instructions for our TargetName.
|
|
populateInstructions();
|
|
}
|
|
|
|
~ARMDEBackend() {
|
|
if (FC) {
|
|
delete FC;
|
|
FC = NULL;
|
|
}
|
|
}
|
|
|
|
void getInstructionsByEnumValue(std::vector<const CodeGenInstruction*>
|
|
&NumberedInstructions) {
|
|
// We must emit the PHI opcode first...
|
|
std::string Namespace = Target.getInstNamespace();
|
|
assert(!Namespace.empty() && "No instructions defined.");
|
|
|
|
NumberedInstructions = Target.getInstructionsByEnumValue();
|
|
}
|
|
|
|
bool populateInstruction(const CodeGenInstruction &CGI, TARGET_NAME_t TN);
|
|
|
|
void populateInstructions();
|
|
|
|
// Emits disassembler code for instruction decoding. This delegates to the
|
|
// FilterChooser instance to do the heavy lifting.
|
|
void emit(raw_ostream &o);
|
|
|
|
protected:
|
|
std::vector<const CodeGenInstruction*> NumberedInstructions;
|
|
std::vector<unsigned> Opcodes;
|
|
// Special case for the ARM chip, which supports ARM and Thumb ISAs.
|
|
// Opcodes2 will be populated with the Thumb opcodes.
|
|
std::vector<unsigned> Opcodes2;
|
|
ARMDecoderEmitter &Frontend;
|
|
CodeGenTarget Target;
|
|
ARMFilterChooser *FC;
|
|
|
|
TARGET_NAME_t TargetName;
|
|
};
|
|
|
|
bool ARMDecoderEmitter::
|
|
ARMDEBackend::populateInstruction(const CodeGenInstruction &CGI,
|
|
TARGET_NAME_t TN) {
|
|
const Record &Def = *CGI.TheDef;
|
|
const StringRef Name = Def.getName();
|
|
uint8_t Form = getByteField(Def, "Form");
|
|
|
|
BitsInit &Bits = getBitsField(Def, "Inst");
|
|
|
|
// If all the bit positions are not specified; do not decode this instruction.
|
|
// We are bound to fail! For proper disassembly, the well-known encoding bits
|
|
// of the instruction must be fully specified.
|
|
//
|
|
// This also removes pseudo instructions from considerations of disassembly,
|
|
// which is a better design and less fragile than the name matchings.
|
|
if (Bits.allInComplete()) return false;
|
|
|
|
// Ignore "asm parser only" instructions.
|
|
if (Def.getValueAsBit("isAsmParserOnly"))
|
|
return false;
|
|
|
|
if (TN == TARGET_ARM) {
|
|
if (Form == ARM_FORMAT_PSEUDO)
|
|
return false;
|
|
if (thumbInstruction(Form))
|
|
return false;
|
|
|
|
// Tail calls are other patterns that generate existing instructions.
|
|
if (Name == "TCRETURNdi" || Name == "TCRETURNdiND" ||
|
|
Name == "TCRETURNri" || Name == "TCRETURNriND" ||
|
|
Name == "TAILJMPd" || Name == "TAILJMPdt" ||
|
|
Name == "TAILJMPdND" || Name == "TAILJMPdNDt" ||
|
|
Name == "TAILJMPr" || Name == "TAILJMPrND" ||
|
|
Name == "MOVr_TC")
|
|
return false;
|
|
|
|
// Delegate ADR disassembly to the more generic ADDri/SUBri instructions.
|
|
if (Name == "ADR")
|
|
return false;
|
|
|
|
//
|
|
// The following special cases are for conflict resolutions.
|
|
//
|
|
|
|
// RSCSri and RSCSrs set the 's' bit, but are not predicated. We are
|
|
// better off using the generic RSCri and RSCrs instructions.
|
|
if (Name == "RSCSri" || Name == "RSCSrs") return false;
|
|
|
|
// A8-598: VEXT
|
|
// Vector Extract extracts elements from the bottom end of the second
|
|
// operand vector and the top end of the first, concatenates them and
|
|
// places the result in the destination vector. The elements of the
|
|
// vectors are treated as being 8-bit bitfields. There is no distinction
|
|
// between data types. The size of the operation can be specified in
|
|
// assembler as vext.size. If the value is 16, 32, or 64, the syntax is
|
|
// a pseudo-instruction for a VEXT instruction specifying the equivalent
|
|
// number of bytes.
|
|
//
|
|
// Variants VEXTd16, VEXTd32, VEXTd8, and VEXTdf are reduced to VEXTd8;
|
|
// variants VEXTq16, VEXTq32, VEXTq8, and VEXTqf are reduced to VEXTq8.
|
|
if (Name == "VEXTd16" || Name == "VEXTd32" || Name == "VEXTdf" ||
|
|
Name == "VEXTq16" || Name == "VEXTq32" || Name == "VEXTqf")
|
|
return false;
|
|
} else if (TN == TARGET_THUMB) {
|
|
if (!thumbInstruction(Form))
|
|
return false;
|
|
|
|
// A8.6.189 STM / STMIA / STMEA -- Encoding T1
|
|
// There's only STMIA_UPD for Thumb1.
|
|
if (Name == "tSTMIA")
|
|
return false;
|
|
|
|
// On Darwin R9 is call-clobbered. Ignore the non-Darwin counterparts.
|
|
if (Name == "tBL" || Name == "tBLXi" || Name == "tBLXr")
|
|
return false;
|
|
|
|
// A8.6.25 BX. Use the generic tBX_Rm, ignore tBX_RET and tBX_RET_vararg.
|
|
if (Name == "tBX_RET" || Name == "tBX_RET_vararg")
|
|
return false;
|
|
|
|
// Ignore the TPsoft (TLS) instructions, which conflict with tBLr9.
|
|
if (Name == "tTPsoft" || Name == "t2TPsoft")
|
|
return false;
|
|
|
|
// Ignore tADR, prefer tADDrPCi.
|
|
if (Name == "tADR")
|
|
return false;
|
|
|
|
// Delegate t2ADR disassembly to the more generic t2ADDri12/t2SUBri12
|
|
// instructions.
|
|
if (Name == "t2ADR")
|
|
return false;
|
|
|
|
// Ignore tADDrSP, tADDspr, and tPICADD, prefer the generic tADDhirr.
|
|
// Ignore t2SUBrSPs, prefer the t2SUB[S]r[r|s].
|
|
// Ignore t2ADDrSPs, prefer the t2ADD[S]r[r|s].
|
|
// Ignore t2ADDrSPi/t2SUBrSPi, which have more generic couterparts.
|
|
// Ignore t2ADDrSPi12/t2SUBrSPi12, which have more generic couterparts
|
|
if (Name == "tADDrSP" || Name == "tADDspr" || Name == "tPICADD" ||
|
|
Name == "t2SUBrSPs" || Name == "t2ADDrSPs" ||
|
|
Name == "t2ADDrSPi" || Name == "t2SUBrSPi" ||
|
|
Name == "t2ADDrSPi12" || Name == "t2SUBrSPi12")
|
|
return false;
|
|
|
|
// FIXME: Use ldr.n to work around a Darwin assembler bug.
|
|
// Introduce a workaround with tLDRpciDIS opcode.
|
|
if (Name == "tLDRpci")
|
|
return false;
|
|
|
|
// Ignore t2LDRDpci, prefer the generic t2LDRDi8, t2LDRD_PRE, t2LDRD_POST.
|
|
if (Name == "t2LDRDpci")
|
|
return false;
|
|
|
|
// Resolve conflicts:
|
|
//
|
|
// tBfar conflicts with tBLr9
|
|
// tPOP_RET/t2LDMIA_RET conflict with tPOP/t2LDM (ditto)
|
|
// tMOVCCi conflicts with tMOVi8
|
|
// tMOVCCr conflicts with tMOVgpr2gpr
|
|
// tSpill conflicts with tSTRspi
|
|
// tLDRcp conflicts with tLDRspi
|
|
// tRestore conflicts with tLDRspi
|
|
// t2MOVCCi16 conflicts with tMOVi16
|
|
if (Name == "tBfar" ||
|
|
Name == "tPOP_RET" || Name == "t2LDMIA_RET" ||
|
|
Name == "tMOVCCi" || Name == "tMOVCCr" ||
|
|
Name == "tSpill" || Name == "tLDRcp" || Name == "tRestore" ||
|
|
Name == "t2MOVCCi16")
|
|
return false;
|
|
}
|
|
|
|
DEBUG({
|
|
// Dumps the instruction encoding format.
|
|
switch (TargetName) {
|
|
case TARGET_ARM:
|
|
case TARGET_THUMB:
|
|
errs() << Name << " " << stringForARMFormat((ARMFormat)Form);
|
|
break;
|
|
}
|
|
|
|
errs() << " ";
|
|
|
|
// Dumps the instruction encoding bits.
|
|
dumpBits(errs(), Bits);
|
|
|
|
errs() << '\n';
|
|
|
|
// Dumps the list of operand info.
|
|
for (unsigned i = 0, e = CGI.Operands.size(); i != e; ++i) {
|
|
const CGIOperandList::OperandInfo &Info = CGI.Operands[i];
|
|
const std::string &OperandName = Info.Name;
|
|
const Record &OperandDef = *Info.Rec;
|
|
|
|
errs() << "\t" << OperandName << " (" << OperandDef.getName() << ")\n";
|
|
}
|
|
});
|
|
|
|
return true;
|
|
}
|
|
|
|
void ARMDecoderEmitter::ARMDEBackend::populateInstructions() {
|
|
getInstructionsByEnumValue(NumberedInstructions);
|
|
|
|
unsigned numUIDs = NumberedInstructions.size();
|
|
if (TargetName == TARGET_ARM) {
|
|
for (unsigned uid = 0; uid < numUIDs; uid++) {
|
|
// filter out intrinsics
|
|
if (!NumberedInstructions[uid]->TheDef->isSubClassOf("InstARM"))
|
|
continue;
|
|
|
|
if (populateInstruction(*NumberedInstructions[uid], TargetName))
|
|
Opcodes.push_back(uid);
|
|
}
|
|
|
|
// Special handling for the ARM chip, which supports two modes of execution.
|
|
// This branch handles the Thumb opcodes.
|
|
for (unsigned uid = 0; uid < numUIDs; uid++) {
|
|
// filter out intrinsics
|
|
if (!NumberedInstructions[uid]->TheDef->isSubClassOf("InstARM")
|
|
&& !NumberedInstructions[uid]->TheDef->isSubClassOf("InstThumb"))
|
|
continue;
|
|
|
|
if (populateInstruction(*NumberedInstructions[uid], TARGET_THUMB))
|
|
Opcodes2.push_back(uid);
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
// For other targets.
|
|
for (unsigned uid = 0; uid < numUIDs; uid++) {
|
|
Record *R = NumberedInstructions[uid]->TheDef;
|
|
if (R->getValueAsString("Namespace") == "TargetOpcode")
|
|
continue;
|
|
|
|
if (populateInstruction(*NumberedInstructions[uid], TargetName))
|
|
Opcodes.push_back(uid);
|
|
}
|
|
}
|
|
|
|
// Emits disassembler code for instruction decoding. This delegates to the
|
|
// FilterChooser instance to do the heavy lifting.
|
|
void ARMDecoderEmitter::ARMDEBackend::emit(raw_ostream &o) {
|
|
switch (TargetName) {
|
|
case TARGET_ARM:
|
|
Frontend.EmitSourceFileHeader("ARM/Thumb Decoders", o);
|
|
break;
|
|
default:
|
|
assert(0 && "Unreachable code!");
|
|
}
|
|
|
|
o << "#include \"llvm/Support/DataTypes.h\"\n";
|
|
o << "#include <assert.h>\n";
|
|
o << '\n';
|
|
o << "namespace llvm {\n\n";
|
|
|
|
ARMFilterChooser::setTargetName(TargetName);
|
|
|
|
switch (TargetName) {
|
|
case TARGET_ARM: {
|
|
// Emit common utility and ARM ISA decoder.
|
|
FC = new ARMFilterChooser(NumberedInstructions, Opcodes);
|
|
// Reset indentation level.
|
|
unsigned Indentation = 0;
|
|
FC->emitTop(o, Indentation);
|
|
delete FC;
|
|
|
|
// Emit Thumb ISA decoder as well.
|
|
ARMFilterChooser::setTargetName(TARGET_THUMB);
|
|
FC = new ARMFilterChooser(NumberedInstructions, Opcodes2);
|
|
// Reset indentation level.
|
|
Indentation = 0;
|
|
FC->emitBot(o, Indentation);
|
|
break;
|
|
}
|
|
default:
|
|
assert(0 && "Unreachable code!");
|
|
}
|
|
|
|
o << "\n} // End llvm namespace \n";
|
|
}
|
|
|
|
/////////////////////////
|
|
// Backend interface //
|
|
/////////////////////////
|
|
|
|
void ARMDecoderEmitter::initBackend()
|
|
{
|
|
Backend = new ARMDEBackend(*this, Records);
|
|
}
|
|
|
|
void ARMDecoderEmitter::run(raw_ostream &o)
|
|
{
|
|
Backend->emit(o);
|
|
}
|
|
|
|
void ARMDecoderEmitter::shutdownBackend()
|
|
{
|
|
delete Backend;
|
|
Backend = NULL;
|
|
}
|