From 48e65fc63076eec4fa527ab7b22fdcb4d8cdbb50 Mon Sep 17 00:00:00 2001 From: Vedant Kumar Date: Tue, 7 Apr 2020 13:09:29 -0700 Subject: [PATCH] MachineFunction: Copy call site info when duplicating insts Summary: Preserve call site info for duplicated instructions. We copy over the call site info in CloneMachineInstrBundle to avoid repeated calls to copyCallSiteInfo in CloneMachineInstr. (Alternatively, we could copy call site info higher up the stack, e.g. into TargetInstrInfo::duplicate, or even into individual backend passes. However, I don't see how that would be safer or more general than the current approach.) Reviewers: aprantl, djtodoro, dstenb Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D77685 --- llvm/lib/CodeGen/MachineFunction.cpp | 5 ++ .../test/CodeGen/X86/taildup-callsiteinfo.mir | 75 +++++++++++++++++++ llvm/unittests/CodeGen/MFCommon.inc | 11 ++- llvm/unittests/CodeGen/MachineInstrTest.cpp | 20 +++++ 4 files changed, 109 insertions(+), 2 deletions(-) create mode 100644 llvm/test/CodeGen/X86/taildup-callsiteinfo.mir diff --git a/llvm/lib/CodeGen/MachineFunction.cpp b/llvm/lib/CodeGen/MachineFunction.cpp index 271fc8c8edbfd..1b89333b98f3e 100644 --- a/llvm/lib/CodeGen/MachineFunction.cpp +++ b/llvm/lib/CodeGen/MachineFunction.cpp @@ -426,6 +426,11 @@ MachineInstr &MachineFunction::CloneMachineInstrBundle(MachineBasicBlock &MBB, break; ++I; } + // Copy over call site info to the cloned instruction if needed. If Orig is in + // a bundle, copyCallSiteInfo takes care of finding the call instruction in + // the bundle. + if (Orig.shouldUpdateCallSiteInfo()) + copyCallSiteInfo(&Orig, FirstClone); return *FirstClone; } diff --git a/llvm/test/CodeGen/X86/taildup-callsiteinfo.mir b/llvm/test/CodeGen/X86/taildup-callsiteinfo.mir new file mode 100644 index 0000000000000..9a1f23a9a4989 --- /dev/null +++ b/llvm/test/CodeGen/X86/taildup-callsiteinfo.mir @@ -0,0 +1,75 @@ +# RUN: llc %s -emit-call-site-info -run-pass=block-placement -tail-dup-placement-threshold=4 -o - | FileCheck %s +# +# Test case adapted from test/CodeGen/X86/taildup-heapallocsite.ll. + +# CHECK-LABEL: callSites: +# CHECK-NEXT: - { bb: 1, offset: 1, fwdArgRegs: +# CHECK-NEXT: - { arg: 0, reg: '$rcx' } } +# CHECK-NEXT: - { bb: 2, offset: 1, fwdArgRegs: +# CHECK-NEXT: - { arg: 0, reg: '$rcx' } } + +--- | + target datalayout = "e-m:w-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" + target triple = "x86_64-pc-windows-msvc19.22.27905" + + define dso_local void @taildupit(i32* readonly %size_ptr) { + entry: + %tobool = icmp eq i32* %size_ptr, null + br i1 %tobool, label %cond.end, label %cond.true + + cond.true: ; preds = %entry + %0 = load i32, i32* %size_ptr, align 4 + br label %cond.end + + cond.end: ; preds = %cond.true, %entry + %cond = phi i32 [ %0, %cond.true ], [ 1, %entry ] + %call = tail call i8* @alloc(i32 %cond) + tail call void @f2() + ret void + } + + declare dso_local i8* @alloc(i32) + + declare dso_local void @f2() + +... +--- +name: taildupit +tracksRegLiveness: true +liveins: + - { reg: '$rcx', virtual-reg: '' } +callSites: + - { bb: 3, offset: 0, fwdArgRegs: + - { arg: 0, reg: '$rcx' } } +body: | + bb.0.entry: + successors: %bb.1(0x30000000), %bb.2(0x50000000) + liveins: $rcx + + $rsp = frame-setup SUB64ri8 $rsp, 40, implicit-def dead $eflags + frame-setup SEH_StackAlloc 40 + frame-setup SEH_EndPrologue + TEST64rr renamable $rcx, renamable $rcx, implicit-def $eflags + JCC_1 %bb.2, 5, implicit killed $eflags + + bb.1: + successors: %bb.3(0x80000000) + + renamable $ecx = MOV32ri 1 + JMP_1 %bb.3 + + bb.2.cond.true: + successors: %bb.3(0x80000000) + liveins: $rcx + + renamable $ecx = MOV32rm killed renamable $rcx, 1, $noreg, 0, $noreg :: (load 4 from %ir.size_ptr) + + bb.3.cond.end: + liveins: $ecx + + CALL64pcrel32 @alloc, csr_win64, implicit $rsp, implicit $ssp, implicit $ecx, implicit-def $rsp, implicit-def $ssp, implicit-def dead $rax + SEH_Epilogue + $rsp = frame-destroy ADD64ri8 $rsp, 40, implicit-def dead $eflags + TAILJMPd64 @f2, csr_win64, implicit $rsp, implicit $ssp, implicit $rsp, implicit $ssp + +... diff --git a/llvm/unittests/CodeGen/MFCommon.inc b/llvm/unittests/CodeGen/MFCommon.inc index 7468ff28fa941..6a31312cd6df1 100644 --- a/llvm/unittests/CodeGen/MFCommon.inc +++ b/llvm/unittests/CodeGen/MFCommon.inc @@ -92,11 +92,18 @@ private: TargetInstrInfo TII; }; +static TargetOptions getTargetOptionsForBogusMachine() { + TargetOptions Opts; + Opts.EmitCallSiteInfo = true; + return Opts; +} + class BogusTargetMachine : public LLVMTargetMachine { public: BogusTargetMachine() - : LLVMTargetMachine(Target(), "", Triple(""), "", "", TargetOptions(), - Reloc::Static, CodeModel::Small, CodeGenOpt::Default), + : LLVMTargetMachine(Target(), "", Triple(""), "", "", + getTargetOptionsForBogusMachine(), Reloc::Static, + CodeModel::Small, CodeGenOpt::Default), ST(*this) {} ~BogusTargetMachine() override {} diff --git a/llvm/unittests/CodeGen/MachineInstrTest.cpp b/llvm/unittests/CodeGen/MachineInstrTest.cpp index 33baaf62efdf7..71c4b8e17f392 100644 --- a/llvm/unittests/CodeGen/MachineInstrTest.cpp +++ b/llvm/unittests/CodeGen/MachineInstrTest.cpp @@ -383,6 +383,26 @@ TEST(MachineInstrExtraInfo, RemoveExtraInfo) { ASSERT_FALSE(MI->getHeapAllocMarker()); } +TEST(MachineInstrClone, CopyCallSiteInfo) { + LLVMContext Ctx; + Module Mod("Module", Ctx); + auto MF = createMachineFunction(Ctx, Mod); + auto MBB = MF->CreateMachineBasicBlock(); + auto MII = MBB->begin(); + + MCInstrDesc MCID = {0, 0, 0, 0, 0, (1ULL << MCID::Call), + 0, nullptr, nullptr, nullptr}; + + MachineFunction::CallSiteInfo CSInfo; + auto MI = MF->CreateMachineInstr(MCID, DebugLoc()); + ASSERT_TRUE(MI->isCandidateForCallSiteEntry()); + MBB->insert(MII, MI); + MF->addCallArgsForwardingRegs(MI, std::move(CSInfo)); + EXPECT_EQ(MF->getCallSitesInfo().size(), 1u); + MF->CloneMachineInstrBundle(*MBB, MBB->end(), *MI); + EXPECT_EQ(MF->getCallSitesInfo().size(), 2u); +} + static_assert(is_trivially_copyable::value, "trivially copyable"); } // end namespace