[Hexagon] Merging nops in to previous packet rather than always creating a new one.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267798 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Colin LeMahieu 2016-04-27 21:37:44 +00:00
parent 42b983d1a7
commit 1baab3bf65
2 changed files with 129 additions and 17 deletions

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@ -11,7 +11,10 @@
#include "HexagonFixupKinds.h"
#include "HexagonMCTargetDesc.h"
#include "MCTargetDesc/HexagonBaseInfo.h"
#include "MCTargetDesc/HexagonMCChecker.h"
#include "MCTargetDesc/HexagonMCCodeEmitter.h"
#include "MCTargetDesc/HexagonMCInstrInfo.h"
#include "MCTargetDesc/HexagonMCShuffler.h"
#include "llvm/MC/MCAsmBackend.h"
#include "llvm/MC/MCAsmLayout.h"
#include "llvm/MC/MCAssembler.h"
@ -41,6 +44,19 @@ class HexagonAsmBackend : public MCAsmBackend {
std::unique_ptr <MCInstrInfo> MCII;
std::unique_ptr <MCInst *> RelaxTarget;
MCInst * Extender;
void ReplaceInstruction(MCCodeEmitter &E, MCRelaxableFragment &RF,
MCInst &HMB) const {
SmallVector<MCFixup, 4> Fixups;
SmallString<256> Code;
raw_svector_ostream VecOS(Code);
E.encodeInstruction(HMB, VecOS, Fixups, RF.getSubtargetInfo());
// Update the fragment.
RF.setInst(HMB);
RF.getContents() = Code;
RF.getFixups() = Fixups;
}
public:
HexagonAsmBackend(const Target &T, uint8_t OSABI, StringRef CPU) :
OSABI(OSABI), MCII (T.createMCInstrInfo()), RelaxTarget(new MCInst *),
@ -530,23 +546,7 @@ public:
///
/// \param Inst - The instruction to test.
bool mayNeedRelaxation(MCInst const &Inst) const override {
assert(HexagonMCInstrInfo::isBundle(Inst));
bool PreviousIsExtender = false;
for (auto const &I : HexagonMCInstrInfo::bundleInstructions(Inst)) {
auto const &Inst = *I.getInst();
if (!PreviousIsExtender) {
if (HexagonMCInstrInfo::isDuplex(*MCII, Inst)) {
if (isInstRelaxable(*Inst.getOperand(0).getInst()) ||
isInstRelaxable(*Inst.getOperand(1).getInst()))
return true;
} else {
if (isInstRelaxable(Inst))
return true;
}
}
PreviousIsExtender = HexagonMCInstrInfo::isImmext(Inst);
}
return false;
return true;
}
/// fixupNeedsRelaxation - Target specific predicate for whether a given
@ -686,6 +686,58 @@ public:
}
return true;
}
void finishLayout(MCAssembler const &Asm,
MCAsmLayout &Layout) const override {
for (auto I : Layout.getSectionOrder()) {
auto &Fragments = I->getFragmentList();
for (auto &J : Fragments) {
switch (J.getKind()) {
default:
break;
case MCFragment::FT_Align: {
auto Size = Asm.computeFragmentSize(Layout, J);
for (auto K = J.getIterator();
K != Fragments.begin() && Size >= HEXAGON_PACKET_SIZE;) {
--K;
switch (K->getKind()) {
default:
break;
case MCFragment::FT_Align: {
// Don't pad before other alignments
Size = 0;
break;
}
case MCFragment::FT_Relaxable: {
auto &RF = cast<MCRelaxableFragment>(*K);
auto &Inst = const_cast<MCInst &>(RF.getInst());
while (Size > 0 && HexagonMCInstrInfo::bundleSize(Inst) < 4) {
MCInst *Nop = new (Asm.getContext()) MCInst;
Nop->setOpcode(Hexagon::A2_nop);
Inst.addOperand(MCOperand::createInst(Nop));
Size -= 4;
if (!HexagonMCChecker(
*MCII, RF.getSubtargetInfo(), Inst, Inst,
*Asm.getContext().getRegisterInfo()).check()) {
Inst.erase(Inst.end() - 1);
Size = 0;
}
}
bool Error = HexagonMCShuffle(*MCII, RF.getSubtargetInfo(), Inst);
//assert(!Error);
(void)Error;
ReplaceInstruction(Asm.getEmitter(), RF, Inst);
Layout.invalidateFragmentsFrom(&RF);
Size = 0; // Only look back one instruction
break;
}
}
}
}
}
}
}
}
};
} // end anonymous namespace

60
test/MC/Hexagon/align.s Normal file
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@ -0,0 +1,60 @@
# RUN: llvm-mc -triple=hexagon -filetype=obj %s | llvm-objdump -d - | FileCheck %s
# Verify that the .align directive emits the proper insn packets.
{ r1 = sub(#1, r1) }
# CHECK: 76414021 { r1 = sub(#1, r1)
# CHECK-NEXT: 7f004000 nop
# CHECK-NEXT: 7f004000 nop
# CHECK-NEXT: 7f00c000 nop }
.align 16
{ r1 = sub(#1, r1)
r2 = sub(#1, r2) }
# CHECK: 76414021 { r1 = sub(#1, r1)
# CHECK-NEXT: 76424022 r2 = sub(#1, r2)
# CHECK-NEXT: 7f004000 nop
# CHECK-NEXT: 7f00c000 nop }
.p2align 5
{ r1 = sub(#1, r1)
r2 = sub(#1, r2)
r3 = sub(#1, r3) }
# CHECK: 76434023 r3 = sub(#1, r3)
# CHECK-NEXT: 7f00c000 nop }
.align 16
{ r1 = sub(#1, r1)
r2 = sub(#1, r2)
r3 = sub(#1, r3)
r4 = sub(#1, r4) }
# Don't pad packets that can't be padded e.g. solo insts
# CHECK: 9200c020 { r0 = vextract(v0,r0) }
r0 = vextract(v0, r0)
.align 128
# CHECK: 76414021 { r1 = sub(#1, r1)
# CHECK-NEXT: 7f00c000 nop }
{ r1 = sub(#1, r1) }
#CHECK: { r1 = sub(#1, r1)
#CHECK: r2 = sub(#1, r2)
#CHECK: r3 = sub(#1, r3) }
.falign
.align 8
{ r1 = sub(#1, r1)
r2 = sub(#1, r2)
r3 = sub(#1, r3) }
# CHECK: { immext(#0)
# CHECK: r0 = sub(##1, r0)
# CHECK: immext(#0)
# CHECK: r1 = sub(##1, r1) }
# CHECK: { nop
# CHECK: nop
# CHECK: nop }
# CHECK: { r0 = sub(#1, r0) }
{ r0 = sub (##1, r0)
r1 = sub (##1, r1) }
.align 16
{ r0 = sub (#1, r0) }