llvm/lib/Target/BPF/BPFInstrInfo.td
Alexei Starovoitov e4bed26281 [bpf] error when unknown bpf helper is called
Emit error when BPF backend sees a call to a global function or to an external symbol.
The kernel verifier only allows calls to predefined helpers from bpf.h
which are defined in 'enum bpf_func_id'. Such calls in assembler must
look like 'call [1-9]+' where number matches bpf_func_id.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292204 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-17 07:26:17 +00:00

580 lines
17 KiB
TableGen

//===-- BPFInstrInfo.td - Target Description for BPF Target ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file describes the BPF instructions in TableGen format.
//
//===----------------------------------------------------------------------===//
include "BPFInstrFormats.td"
// Instruction Operands and Patterns
// These are target-independent nodes, but have target-specific formats.
def SDT_BPFCallSeqStart : SDCallSeqStart<[SDTCisVT<0, iPTR>]>;
def SDT_BPFCallSeqEnd : SDCallSeqEnd<[SDTCisVT<0, iPTR>, SDTCisVT<1, iPTR>]>;
def SDT_BPFCall : SDTypeProfile<0, -1, [SDTCisVT<0, iPTR>]>;
def SDT_BPFSetFlag : SDTypeProfile<0, 3, [SDTCisSameAs<0, 1>]>;
def SDT_BPFSelectCC : SDTypeProfile<1, 5, [SDTCisSameAs<1, 2>,
SDTCisSameAs<0, 4>,
SDTCisSameAs<4, 5>]>;
def SDT_BPFBrCC : SDTypeProfile<0, 4, [SDTCisSameAs<0, 1>,
SDTCisVT<3, OtherVT>]>;
def SDT_BPFWrapper : SDTypeProfile<1, 1, [SDTCisSameAs<0, 1>,
SDTCisPtrTy<0>]>;
def BPFcall : SDNode<"BPFISD::CALL", SDT_BPFCall,
[SDNPHasChain, SDNPOptInGlue, SDNPOutGlue,
SDNPVariadic]>;
def BPFretflag : SDNode<"BPFISD::RET_FLAG", SDTNone,
[SDNPHasChain, SDNPOptInGlue, SDNPVariadic]>;
def BPFcallseq_start: SDNode<"ISD::CALLSEQ_START", SDT_BPFCallSeqStart,
[SDNPHasChain, SDNPOutGlue]>;
def BPFcallseq_end : SDNode<"ISD::CALLSEQ_END", SDT_BPFCallSeqEnd,
[SDNPHasChain, SDNPOptInGlue, SDNPOutGlue]>;
def BPFbrcc : SDNode<"BPFISD::BR_CC", SDT_BPFBrCC,
[SDNPHasChain, SDNPOutGlue, SDNPInGlue]>;
def BPFselectcc : SDNode<"BPFISD::SELECT_CC", SDT_BPFSelectCC, [SDNPInGlue]>;
def BPFWrapper : SDNode<"BPFISD::Wrapper", SDT_BPFWrapper>;
def brtarget : Operand<OtherVT>;
def calltarget : Operand<i64>;
def u64imm : Operand<i64> {
let PrintMethod = "printImm64Operand";
}
def i64immSExt32 : PatLeaf<(imm),
[{return isInt<32>(N->getSExtValue()); }]>;
// Addressing modes.
def ADDRri : ComplexPattern<i64, 2, "SelectAddr", [], []>;
def FIri : ComplexPattern<i64, 2, "SelectFIAddr", [add, or], []>;
// Address operands
def MEMri : Operand<i64> {
let PrintMethod = "printMemOperand";
let EncoderMethod = "getMemoryOpValue";
let DecoderMethod = "decodeMemoryOpValue";
let MIOperandInfo = (ops GPR, i16imm);
}
// Conditional code predicates - used for pattern matching for jump instructions
def BPF_CC_EQ : PatLeaf<(imm),
[{return (N->getZExtValue() == ISD::SETEQ);}]>;
def BPF_CC_NE : PatLeaf<(imm),
[{return (N->getZExtValue() == ISD::SETNE);}]>;
def BPF_CC_GE : PatLeaf<(imm),
[{return (N->getZExtValue() == ISD::SETGE);}]>;
def BPF_CC_GT : PatLeaf<(imm),
[{return (N->getZExtValue() == ISD::SETGT);}]>;
def BPF_CC_GTU : PatLeaf<(imm),
[{return (N->getZExtValue() == ISD::SETUGT);}]>;
def BPF_CC_GEU : PatLeaf<(imm),
[{return (N->getZExtValue() == ISD::SETUGE);}]>;
// jump instructions
class JMP_RR<bits<4> Opc, string OpcodeStr, PatLeaf Cond>
: InstBPF<(outs), (ins GPR:$dst, GPR:$src, brtarget:$BrDst),
"if $dst "#OpcodeStr#" $src goto $BrDst",
[(BPFbrcc i64:$dst, i64:$src, Cond, bb:$BrDst)]> {
bits<4> op;
bits<1> BPFSrc;
bits<4> dst;
bits<4> src;
bits<16> BrDst;
let Inst{63-60} = op;
let Inst{59} = BPFSrc;
let Inst{55-52} = src;
let Inst{51-48} = dst;
let Inst{47-32} = BrDst;
let op = Opc;
let BPFSrc = 1;
let BPFClass = 5; // BPF_JMP
}
class JMP_RI<bits<4> Opc, string OpcodeStr, PatLeaf Cond>
: InstBPF<(outs), (ins GPR:$dst, i64imm:$imm, brtarget:$BrDst),
"if $dst "#OpcodeStr#" $imm goto $BrDst",
[(BPFbrcc i64:$dst, i64immSExt32:$imm, Cond, bb:$BrDst)]> {
bits<4> op;
bits<1> BPFSrc;
bits<4> dst;
bits<16> BrDst;
bits<32> imm;
let Inst{63-60} = op;
let Inst{59} = BPFSrc;
let Inst{51-48} = dst;
let Inst{47-32} = BrDst;
let Inst{31-0} = imm;
let op = Opc;
let BPFSrc = 0;
let BPFClass = 5; // BPF_JMP
}
multiclass J<bits<4> Opc, string OpcodeStr, PatLeaf Cond> {
def _rr : JMP_RR<Opc, OpcodeStr, Cond>;
def _ri : JMP_RI<Opc, OpcodeStr, Cond>;
}
let isBranch = 1, isTerminator = 1, hasDelaySlot=0 in {
// cmp+goto instructions
defm JEQ : J<0x1, "==", BPF_CC_EQ>;
defm JUGT : J<0x2, ">", BPF_CC_GTU>;
defm JUGE : J<0x3, ">=", BPF_CC_GEU>;
defm JNE : J<0x5, "!=", BPF_CC_NE>;
defm JSGT : J<0x6, "s>", BPF_CC_GT>;
defm JSGE : J<0x7, "s>=", BPF_CC_GE>;
}
// ALU instructions
class ALU_RI<bits<4> Opc, string OpcodeStr, SDNode OpNode>
: InstBPF<(outs GPR:$dst), (ins GPR:$src2, i64imm:$imm),
"$dst "#OpcodeStr#" $imm",
[(set GPR:$dst, (OpNode GPR:$src2, i64immSExt32:$imm))]> {
bits<4> op;
bits<1> BPFSrc;
bits<4> dst;
bits<32> imm;
let Inst{63-60} = op;
let Inst{59} = BPFSrc;
let Inst{51-48} = dst;
let Inst{31-0} = imm;
let op = Opc;
let BPFSrc = 0;
let BPFClass = 7; // BPF_ALU64
}
class ALU_RR<bits<4> Opc, string OpcodeStr, SDNode OpNode>
: InstBPF<(outs GPR:$dst), (ins GPR:$src2, GPR:$src),
"$dst "#OpcodeStr#" $src",
[(set GPR:$dst, (OpNode i64:$src2, i64:$src))]> {
bits<4> op;
bits<1> BPFSrc;
bits<4> dst;
bits<4> src;
let Inst{63-60} = op;
let Inst{59} = BPFSrc;
let Inst{55-52} = src;
let Inst{51-48} = dst;
let op = Opc;
let BPFSrc = 1;
let BPFClass = 7; // BPF_ALU64
}
multiclass ALU<bits<4> Opc, string OpcodeStr, SDNode OpNode> {
def _rr : ALU_RR<Opc, OpcodeStr, OpNode>;
def _ri : ALU_RI<Opc, OpcodeStr, OpNode>;
}
let Constraints = "$dst = $src2" in {
let isAsCheapAsAMove = 1 in {
defm ADD : ALU<0x0, "+=", add>;
defm SUB : ALU<0x1, "-=", sub>;
defm OR : ALU<0x4, "|=", or>;
defm AND : ALU<0x5, "&=", and>;
defm SLL : ALU<0x6, "<<=", shl>;
defm SRL : ALU<0x7, ">>=", srl>;
defm XOR : ALU<0xa, "^=", xor>;
defm SRA : ALU<0xc, "s>>=", sra>;
}
defm MUL : ALU<0x2, "*=", mul>;
defm DIV : ALU<0x3, "/=", udiv>;
}
class MOV_RR<string OpcodeStr>
: InstBPF<(outs GPR:$dst), (ins GPR:$src),
"$dst "#OpcodeStr#" $src",
[]> {
bits<4> op;
bits<1> BPFSrc;
bits<4> dst;
bits<4> src;
let Inst{63-60} = op;
let Inst{59} = BPFSrc;
let Inst{55-52} = src;
let Inst{51-48} = dst;
let op = 0xb; // BPF_MOV
let BPFSrc = 1; // BPF_X
let BPFClass = 7; // BPF_ALU64
}
class MOV_RI<string OpcodeStr>
: InstBPF<(outs GPR:$dst), (ins i64imm:$imm),
"$dst "#OpcodeStr#" $imm",
[(set GPR:$dst, (i64 i64immSExt32:$imm))]> {
bits<4> op;
bits<1> BPFSrc;
bits<4> dst;
bits<32> imm;
let Inst{63-60} = op;
let Inst{59} = BPFSrc;
let Inst{51-48} = dst;
let Inst{31-0} = imm;
let op = 0xb; // BPF_MOV
let BPFSrc = 0; // BPF_K
let BPFClass = 7; // BPF_ALU64
}
class LD_IMM64<bits<4> Pseudo, string OpcodeStr>
: InstBPF<(outs GPR:$dst), (ins u64imm:$imm),
"$dst "#OpcodeStr#" ${imm}ll",
[(set GPR:$dst, (i64 imm:$imm))]> {
bits<3> mode;
bits<2> size;
bits<4> dst;
bits<64> imm;
let Inst{63-61} = mode;
let Inst{60-59} = size;
let Inst{51-48} = dst;
let Inst{55-52} = Pseudo;
let Inst{47-32} = 0;
let Inst{31-0} = imm{31-0};
let mode = 0; // BPF_IMM
let size = 3; // BPF_DW
let BPFClass = 0; // BPF_LD
}
let isReMaterializable = 1, isAsCheapAsAMove = 1 in {
def LD_imm64 : LD_IMM64<0, "=">;
def MOV_rr : MOV_RR<"=">;
def MOV_ri : MOV_RI<"=">;
}
def FI_ri
: InstBPF<(outs GPR:$dst), (ins MEMri:$addr),
"lea\t$dst, $addr",
[(set i64:$dst, FIri:$addr)]> {
// This is a tentative instruction, and will be replaced
// with MOV_rr and ADD_ri in PEI phase
let Inst{63-61} = 0;
let Inst{60-59} = 3;
let Inst{51-48} = 0;
let Inst{55-52} = 2;
let Inst{47-32} = 0;
let Inst{31-0} = 0;
let BPFClass = 0;
}
def LD_pseudo
: InstBPF<(outs GPR:$dst), (ins i64imm:$pseudo, u64imm:$imm),
"ld_pseudo\t$dst, $pseudo, $imm",
[(set GPR:$dst, (int_bpf_pseudo imm:$pseudo, imm:$imm))]> {
bits<3> mode;
bits<2> size;
bits<4> dst;
bits<64> imm;
bits<4> pseudo;
let Inst{63-61} = mode;
let Inst{60-59} = size;
let Inst{51-48} = dst;
let Inst{55-52} = pseudo;
let Inst{47-32} = 0;
let Inst{31-0} = imm{31-0};
let mode = 0; // BPF_IMM
let size = 3; // BPF_DW
let BPFClass = 0; // BPF_LD
}
// STORE instructions
class STORE<bits<2> SizeOp, string OpcodeStr, list<dag> Pattern>
: InstBPF<(outs), (ins GPR:$src, MEMri:$addr),
"*("#OpcodeStr#" *)($addr) = $src", Pattern> {
bits<3> mode;
bits<2> size;
bits<4> src;
bits<20> addr;
let Inst{63-61} = mode;
let Inst{60-59} = size;
let Inst{51-48} = addr{19-16}; // base reg
let Inst{55-52} = src;
let Inst{47-32} = addr{15-0}; // offset
let mode = 3; // BPF_MEM
let size = SizeOp;
let BPFClass = 3; // BPF_STX
}
class STOREi64<bits<2> Opc, string OpcodeStr, PatFrag OpNode>
: STORE<Opc, OpcodeStr, [(OpNode i64:$src, ADDRri:$addr)]>;
def STW : STOREi64<0x0, "u32", truncstorei32>;
def STH : STOREi64<0x1, "u16", truncstorei16>;
def STB : STOREi64<0x2, "u8", truncstorei8>;
def STD : STOREi64<0x3, "u64", store>;
// LOAD instructions
class LOAD<bits<2> SizeOp, string OpcodeStr, list<dag> Pattern>
: InstBPF<(outs GPR:$dst), (ins MEMri:$addr),
"$dst = *("#OpcodeStr#" *)($addr)", Pattern> {
bits<3> mode;
bits<2> size;
bits<4> dst;
bits<20> addr;
let Inst{63-61} = mode;
let Inst{60-59} = size;
let Inst{51-48} = dst;
let Inst{55-52} = addr{19-16};
let Inst{47-32} = addr{15-0};
let mode = 3; // BPF_MEM
let size = SizeOp;
let BPFClass = 1; // BPF_LDX
}
class LOADi64<bits<2> SizeOp, string OpcodeStr, PatFrag OpNode>
: LOAD<SizeOp, OpcodeStr, [(set i64:$dst, (OpNode ADDRri:$addr))]>;
def LDW : LOADi64<0x0, "u32", zextloadi32>;
def LDH : LOADi64<0x1, "u16", zextloadi16>;
def LDB : LOADi64<0x2, "u8", zextloadi8>;
def LDD : LOADi64<0x3, "u64", load>;
class BRANCH<bits<4> Opc, string OpcodeStr, list<dag> Pattern>
: InstBPF<(outs), (ins brtarget:$BrDst),
!strconcat(OpcodeStr, " $BrDst"), Pattern> {
bits<4> op;
bits<16> BrDst;
bits<1> BPFSrc;
let Inst{63-60} = op;
let Inst{59} = BPFSrc;
let Inst{47-32} = BrDst;
let op = Opc;
let BPFSrc = 0;
let BPFClass = 5; // BPF_JMP
}
class CALL<string OpcodeStr>
: InstBPF<(outs), (ins calltarget:$BrDst),
!strconcat(OpcodeStr, " $BrDst"), []> {
bits<4> op;
bits<32> BrDst;
bits<1> BPFSrc;
let Inst{63-60} = op;
let Inst{59} = BPFSrc;
let Inst{31-0} = BrDst;
let op = 8; // BPF_CALL
let BPFSrc = 0;
let BPFClass = 5; // BPF_JMP
}
// Jump always
let isBranch = 1, isTerminator = 1, hasDelaySlot=0, isBarrier = 1 in {
def JMP : BRANCH<0x0, "goto", [(br bb:$BrDst)]>;
}
// Jump and link
let isCall=1, hasDelaySlot=0, Uses = [R11],
// Potentially clobbered registers
Defs = [R0, R1, R2, R3, R4, R5] in {
def JAL : CALL<"call">;
}
class NOP_I<string OpcodeStr>
: InstBPF<(outs), (ins i32imm:$imm),
!strconcat(OpcodeStr, "\t$imm"), []> {
// mov r0, r0 == nop
bits<4> op;
bits<1> BPFSrc;
bits<4> dst;
bits<4> src;
let Inst{63-60} = op;
let Inst{59} = BPFSrc;
let Inst{55-52} = src;
let Inst{51-48} = dst;
let op = 0xb; // BPF_MOV
let BPFSrc = 1; // BPF_X
let BPFClass = 7; // BPF_ALU64
let src = 0; // R0
let dst = 0; // R0
}
let hasSideEffects = 0 in
def NOP : NOP_I<"nop">;
class RET<string OpcodeStr>
: InstBPF<(outs), (ins),
!strconcat(OpcodeStr, ""), [(BPFretflag)]> {
bits<4> op;
let Inst{63-60} = op;
let Inst{59} = 0;
let Inst{31-0} = 0;
let op = 9; // BPF_EXIT
let BPFClass = 5; // BPF_JMP
}
let isReturn = 1, isTerminator = 1, hasDelaySlot=0, isBarrier = 1,
isNotDuplicable = 1 in {
def RET : RET<"exit">;
}
// ADJCALLSTACKDOWN/UP pseudo insns
let Defs = [R11], Uses = [R11] in {
def ADJCALLSTACKDOWN : Pseudo<(outs), (ins i64imm:$amt),
"#ADJCALLSTACKDOWN $amt",
[(BPFcallseq_start timm:$amt)]>;
def ADJCALLSTACKUP : Pseudo<(outs), (ins i64imm:$amt1, i64imm:$amt2),
"#ADJCALLSTACKUP $amt1 $amt2",
[(BPFcallseq_end timm:$amt1, timm:$amt2)]>;
}
let usesCustomInserter = 1 in {
def Select : Pseudo<(outs GPR:$dst),
(ins GPR:$lhs, GPR:$rhs, i64imm:$imm, GPR:$src, GPR:$src2),
"# Select PSEUDO $dst = $lhs $imm $rhs ? $src : $src2",
[(set i64:$dst,
(BPFselectcc i64:$lhs, i64:$rhs, (i64 imm:$imm), i64:$src, i64:$src2))]>;
}
// load 64-bit global addr into register
def : Pat<(BPFWrapper tglobaladdr:$in), (LD_imm64 tglobaladdr:$in)>;
// 0xffffFFFF doesn't fit into simm32, optimize common case
def : Pat<(i64 (and (i64 GPR:$src), 0xffffFFFF)),
(SRL_ri (SLL_ri (i64 GPR:$src), 32), 32)>;
// Calls
def : Pat<(BPFcall tglobaladdr:$dst), (JAL tglobaladdr:$dst)>;
def : Pat<(BPFcall texternalsym:$dst), (JAL texternalsym:$dst)>;
def : Pat<(BPFcall imm:$dst), (JAL imm:$dst)>;
// Loads
def : Pat<(extloadi8 ADDRri:$src), (i64 (LDB ADDRri:$src))>;
def : Pat<(extloadi16 ADDRri:$src), (i64 (LDH ADDRri:$src))>;
def : Pat<(extloadi32 ADDRri:$src), (i64 (LDW ADDRri:$src))>;
// Atomics
class XADD<bits<2> SizeOp, string OpcodeStr, PatFrag OpNode>
: InstBPF<(outs GPR:$dst), (ins MEMri:$addr, GPR:$val),
"lock *("#OpcodeStr#" *)($addr) += $val",
[(set GPR:$dst, (OpNode ADDRri:$addr, GPR:$val))]> {
bits<3> mode;
bits<2> size;
bits<4> dst;
bits<20> addr;
let Inst{63-61} = mode;
let Inst{60-59} = size;
let Inst{51-48} = addr{19-16}; // base reg
let Inst{55-52} = dst;
let Inst{47-32} = addr{15-0}; // offset
let mode = 6; // BPF_XADD
let size = SizeOp;
let BPFClass = 3; // BPF_STX
}
let Constraints = "$dst = $val" in {
def XADD32 : XADD<0, "u32", atomic_load_add_32>;
def XADD64 : XADD<3, "u64", atomic_load_add_64>;
// undefined def XADD16 : XADD<1, "xadd16", atomic_load_add_16>;
// undefined def XADD8 : XADD<2, "xadd8", atomic_load_add_8>;
}
// bswap16, bswap32, bswap64
class BSWAP<bits<32> SizeOp, string OpcodeStr, list<dag> Pattern>
: InstBPF<(outs GPR:$dst), (ins GPR:$src),
!strconcat(OpcodeStr, "\t$dst"),
Pattern> {
bits<4> op;
bits<1> BPFSrc;
bits<4> dst;
bits<32> imm;
let Inst{63-60} = op;
let Inst{59} = BPFSrc;
let Inst{51-48} = dst;
let Inst{31-0} = imm;
let op = 0xd; // BPF_END
let BPFSrc = 1; // BPF_TO_BE (TODO: use BPF_TO_LE for big-endian target)
let BPFClass = 4; // BPF_ALU
let imm = SizeOp;
}
let Constraints = "$dst = $src" in {
def BSWAP16 : BSWAP<16, "bswap16", [(set GPR:$dst, (srl (bswap GPR:$src), (i64 48)))]>;
def BSWAP32 : BSWAP<32, "bswap32", [(set GPR:$dst, (srl (bswap GPR:$src), (i64 32)))]>;
def BSWAP64 : BSWAP<64, "bswap64", [(set GPR:$dst, (bswap GPR:$src))]>;
}
let Defs = [R0, R1, R2, R3, R4, R5], Uses = [R6], hasSideEffects = 1,
hasExtraDefRegAllocReq = 1, hasExtraSrcRegAllocReq = 1, mayLoad = 1 in {
class LOAD_ABS<bits<2> SizeOp, string OpcodeStr, Intrinsic OpNode>
: InstBPF<(outs), (ins GPR:$skb, i64imm:$imm),
"r0 = *("#OpcodeStr#" *)skb[$imm]",
[(set R0, (OpNode GPR:$skb, i64immSExt32:$imm))]> {
bits<3> mode;
bits<2> size;
bits<32> imm;
let Inst{63-61} = mode;
let Inst{60-59} = size;
let Inst{31-0} = imm;
let mode = 1; // BPF_ABS
let size = SizeOp;
let BPFClass = 0; // BPF_LD
}
class LOAD_IND<bits<2> SizeOp, string OpcodeStr, Intrinsic OpNode>
: InstBPF<(outs), (ins GPR:$skb, GPR:$val),
"r0 = *("#OpcodeStr#" *)skb[$val]",
[(set R0, (OpNode GPR:$skb, GPR:$val))]> {
bits<3> mode;
bits<2> size;
bits<4> val;
let Inst{63-61} = mode;
let Inst{60-59} = size;
let Inst{55-52} = val;
let mode = 2; // BPF_IND
let size = SizeOp;
let BPFClass = 0; // BPF_LD
}
}
def LD_ABS_B : LOAD_ABS<2, "u8", int_bpf_load_byte>;
def LD_ABS_H : LOAD_ABS<1, "u16", int_bpf_load_half>;
def LD_ABS_W : LOAD_ABS<0, "u32", int_bpf_load_word>;
def LD_IND_B : LOAD_IND<2, "u8", int_bpf_load_byte>;
def LD_IND_H : LOAD_IND<1, "u16", int_bpf_load_half>;
def LD_IND_W : LOAD_IND<0, "u32", int_bpf_load_word>;