[llvm] Merge sourcelocation in CSEMIRBuilder::getDominatingInstrForID. (PR #90922)
Shubham Sandeep Rastogi via llvm-commits
llvm-commits at lists.llvm.org
Tue May 7 11:20:22 PDT 2024
https://github.com/rastogishubham updated https://github.com/llvm/llvm-project/pull/90922
>From 7d191558482a006c8aa629753696458251272f9f Mon Sep 17 00:00:00 2001
From: Shubham Sandeep Rastogi <srastogi22 at apple.com>
Date: Thu, 2 May 2024 15:17:12 -0700
Subject: [PATCH] Merge sourcelocation in
CSEMIRBuilder::getDominatingInstrForID.
Make sure to merge the sourcelocation of the Dominating Instruction that
is hoisted in a basic block in the CSEMIRBuilder in the legalizer pass.
If this is not done, we can have a incorrect line table entry that makes
the instruction pointer jump around.
For example the line table without this patch looks like:
Address Line Column File ISA Discriminator OpIndex Flags
------------------ ------ ------ ------ --- ------------- ------- -------------
0x0000000000000000 0 0 1 0 0 0 is_stmt
0x0000000000000010 11 14 1 0 0 0 is_stmt prologue_end
0x0000000000000028 12 1 1 0 0 0 is_stmt
0x000000000000002c 12 15 1 0 0 0
0x000000000000004c 12 13 1 0 0 0
0x000000000000005c 13 1 1 0 0 0 is_stmt
0x0000000000000064 12 13 1 0 0 0 is_stmt
0x000000000000007c 13 7 1 0 0 0 is_stmt
0x00000000000000c8 13 1 1 0 0 0
0x00000000000000e8 13 1 1 0 0 0 epilogue_begin
0x00000000000000f8 13 1 1 0 0 0 end_sequence
The line table entry for 0x000000000000005c should be 0
---
.../llvm/CodeGen/GlobalISel/CSEMIRBuilder.h | 7 +++--
.../GlobalISel/LegalizationArtifactCombiner.h | 6 +++-
.../CodeGen/GlobalISel/MachineIRBuilder.h | 10 +++++--
llvm/lib/CodeGen/GlobalISel/CSEMIRBuilder.cpp | 20 +++++++++----
.../CodeGen/GlobalISel/MachineIRBuilder.cpp | 8 +++--
.../DebugInfo/merge-locations-legalizer.mir | 30 +++++++++++++++++++
6 files changed, 67 insertions(+), 14 deletions(-)
create mode 100644 llvm/test/DebugInfo/merge-locations-legalizer.mir
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/CSEMIRBuilder.h b/llvm/include/llvm/CodeGen/GlobalISel/CSEMIRBuilder.h
index 488df12f13f8d..8058751ee295c 100644
--- a/llvm/include/llvm/CodeGen/GlobalISel/CSEMIRBuilder.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/CSEMIRBuilder.h
@@ -48,7 +48,8 @@ class CSEMIRBuilder : public MachineIRBuilder {
/// current insertion point and return it. If not found, return Null
/// MachineInstrBuilder.
MachineInstrBuilder getDominatingInstrForID(FoldingSetNodeID &ID,
- void *&NodeInsertPos);
+ void *&NodeInsertPos,
+ DILocation *Location = nullptr);
/// Simple check if we can CSE (we have the CSEInfo) or if this Opcode is
/// safe to CSE.
bool canPerformCSEForOpc(unsigned Opc) const;
@@ -97,8 +98,8 @@ class CSEMIRBuilder : public MachineIRBuilder {
// Bring in the other overload from the base class.
using MachineIRBuilder::buildConstant;
- MachineInstrBuilder buildConstant(const DstOp &Res,
- const ConstantInt &Val) override;
+ MachineInstrBuilder buildConstant(const DstOp &Res, const ConstantInt &Val,
+ DILocation *Location = nullptr) override;
// Bring in the other overload from the base class.
using MachineIRBuilder::buildFConstant;
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/LegalizationArtifactCombiner.h b/llvm/include/llvm/CodeGen/GlobalISel/LegalizationArtifactCombiner.h
index 305bef7dd3ea6..fc9232eeae0b6 100644
--- a/llvm/include/llvm/CodeGen/GlobalISel/LegalizationArtifactCombiner.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/LegalizationArtifactCombiner.h
@@ -26,6 +26,7 @@
#include "llvm/CodeGen/Register.h"
#include "llvm/CodeGen/TargetOpcodes.h"
#include "llvm/IR/Constants.h"
+#include "llvm/IR/DebugInfoMetadata.h"
#include "llvm/Support/Debug.h"
#define DEBUG_TYPE "legalizer"
@@ -99,8 +100,11 @@ class LegalizationArtifactCombiner {
const LLT DstTy = MRI.getType(DstReg);
if (isInstLegal({TargetOpcode::G_CONSTANT, {DstTy}})) {
auto &CstVal = SrcMI->getOperand(1);
+ auto *MergedLocation = DILocation::getMergedLocation(
+ MI.getDebugLoc().get(), SrcMI->getDebugLoc().get());
Builder.buildConstant(
- DstReg, CstVal.getCImm()->getValue().sext(DstTy.getSizeInBits()));
+ DstReg, CstVal.getCImm()->getValue().sext(DstTy.getSizeInBits()),
+ MergedLocation);
UpdatedDefs.push_back(DstReg);
markInstAndDefDead(MI, *SrcMI, DeadInsts);
return true;
diff --git a/llvm/include/llvm/CodeGen/GlobalISel/MachineIRBuilder.h b/llvm/include/llvm/CodeGen/GlobalISel/MachineIRBuilder.h
index e15f7a7172e1a..d8b7f63226cf8 100644
--- a/llvm/include/llvm/CodeGen/GlobalISel/MachineIRBuilder.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/MachineIRBuilder.h
@@ -243,6 +243,10 @@ class MachineIRBuilder {
}
public:
+ /// This is the merged location of an instruction which is a result of a fold
+ /// in the legalizer.
+ DILocation *Location = nullptr;
+
/// Some constructors for easy use.
MachineIRBuilder() = default;
MachineIRBuilder(MachineFunction &MF) { setMF(MF); }
@@ -857,7 +861,8 @@ class MachineIRBuilder {
///
/// \return The newly created instruction.
virtual MachineInstrBuilder buildConstant(const DstOp &Res,
- const ConstantInt &Val);
+ const ConstantInt &Val,
+ DILocation *Location = nullptr);
/// Build and insert \p Res = G_CONSTANT \p Val
///
@@ -868,7 +873,8 @@ class MachineIRBuilder {
///
/// \return The newly created instruction.
MachineInstrBuilder buildConstant(const DstOp &Res, int64_t Val);
- MachineInstrBuilder buildConstant(const DstOp &Res, const APInt &Val);
+ MachineInstrBuilder buildConstant(const DstOp &Res, const APInt &Val,
+ DILocation *Location = nullptr);
/// Build and insert \p Res = G_FCONSTANT \p Val
///
diff --git a/llvm/lib/CodeGen/GlobalISel/CSEMIRBuilder.cpp b/llvm/lib/CodeGen/GlobalISel/CSEMIRBuilder.cpp
index 551ba1e6036c1..d0685304fff83 100644
--- a/llvm/lib/CodeGen/GlobalISel/CSEMIRBuilder.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/CSEMIRBuilder.cpp
@@ -34,9 +34,8 @@ bool CSEMIRBuilder::dominates(MachineBasicBlock::const_iterator A,
return &*I == A;
}
-MachineInstrBuilder
-CSEMIRBuilder::getDominatingInstrForID(FoldingSetNodeID &ID,
- void *&NodeInsertPos) {
+MachineInstrBuilder CSEMIRBuilder::getDominatingInstrForID(
+ FoldingSetNodeID &ID, void *&NodeInsertPos, DILocation *Location) {
GISelCSEInfo *CSEInfo = getCSEInfo();
assert(CSEInfo && "Can't get here without setting CSEInfo");
MachineBasicBlock *CurMBB = &getMBB();
@@ -51,6 +50,16 @@ CSEMIRBuilder::getDominatingInstrForID(FoldingSetNodeID &ID,
// this builder will have the def ready.
setInsertPt(*CurMBB, std::next(MII));
} else if (!dominates(MI, CurrPos)) {
+ // Location represents the DILocation of an instruction (or merged
+ // location of instructions, if multiple instructions were folded) at the
+ // insertion point where MI is going to be moved to, since MI is going to
+ // be moved, it's DILocation needs to be updated to make sure the line
+ // table is correct.
+ if (Location) {
+ auto *Loc =
+ DILocation::getMergedLocation(Location, MI->getDebugLoc().get());
+ MI->setDebugLoc(Loc);
+ }
CurMBB->splice(CurrPos, CurMBB, MI);
}
return MachineInstrBuilder(getMF(), MI);
@@ -321,7 +330,8 @@ MachineInstrBuilder CSEMIRBuilder::buildInstr(unsigned Opc,
}
MachineInstrBuilder CSEMIRBuilder::buildConstant(const DstOp &Res,
- const ConstantInt &Val) {
+ const ConstantInt &Val,
+ DILocation *Location) {
constexpr unsigned Opc = TargetOpcode::G_CONSTANT;
if (!canPerformCSEForOpc(Opc))
return MachineIRBuilder::buildConstant(Res, Val);
@@ -337,7 +347,7 @@ MachineInstrBuilder CSEMIRBuilder::buildConstant(const DstOp &Res,
profileMBBOpcode(ProfBuilder, Opc);
profileDstOp(Res, ProfBuilder);
ProfBuilder.addNodeIDMachineOperand(MachineOperand::CreateCImm(&Val));
- MachineInstrBuilder MIB = getDominatingInstrForID(ID, InsertPos);
+ MachineInstrBuilder MIB = getDominatingInstrForID(ID, InsertPos, Location);
if (MIB) {
// Handle generating copies here.
return generateCopiesIfRequired({Res}, MIB);
diff --git a/llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp b/llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
index 2e8407813ba64..561f356a3bc24 100644
--- a/llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
@@ -315,7 +315,8 @@ MachineInstrBuilder MachineIRBuilder::buildCopy(const DstOp &Res,
}
MachineInstrBuilder MachineIRBuilder::buildConstant(const DstOp &Res,
- const ConstantInt &Val) {
+ const ConstantInt &Val,
+ DILocation *Location) {
LLT Ty = Res.getLLTTy(*getMRI());
LLT EltTy = Ty.getScalarType();
assert(EltTy.getScalarSizeInBits() == Val.getBitWidth() &&
@@ -376,9 +377,10 @@ MachineInstrBuilder MachineIRBuilder::buildFConstant(const DstOp &Res,
}
MachineInstrBuilder MachineIRBuilder::buildConstant(const DstOp &Res,
- const APInt &Val) {
+ const APInt &Val,
+ DILocation *Location) {
ConstantInt *CI = ConstantInt::get(getMF().getFunction().getContext(), Val);
- return buildConstant(Res, *CI);
+ return buildConstant(Res, *CI, Location);
}
MachineInstrBuilder MachineIRBuilder::buildFConstant(const DstOp &Res,
diff --git a/llvm/test/DebugInfo/merge-locations-legalizer.mir b/llvm/test/DebugInfo/merge-locations-legalizer.mir
new file mode 100644
index 0000000000000..fb57f63fd6a0c
--- /dev/null
+++ b/llvm/test/DebugInfo/merge-locations-legalizer.mir
@@ -0,0 +1,30 @@
+# This test checks to make sure that when an instruction (%3 in the test) is
+# moved due to matching a result of a fold of two other instructions
+# (%1, and %2 in the test) in the legalizer, the DILocation of the
+# instruction that is moved (%3) is updated appropriately.
+
+# RUN: llc %s -run-pass=legalizer -o - | FileCheck %s
+# CHECK-NOT: %2:_(s32) = G_CONSTANT i32 0, debug-location !DILocation(line: 13
+# CHECK: %2:_(s32) = G_CONSTANT i32 0, debug-location !DILocation(line: 0,
+--- |
+
+ define i32 @main(i32 %0, ptr %1) #0 !dbg !57 {
+ entry:
+ ret i32 0, !dbg !71
+ }
+ !3 = !DIFile(filename: "main.swift", directory: "/Volumes/Data/swift")
+ !23 = distinct !DICompileUnit(language: DW_LANG_Swift, file: !3, sdk: "blah.sdk")
+ !57 = distinct !DISubprogram(name: "main", unit: !23)
+ !64 = distinct !DILexicalBlock(scope: !57, column: 1)
+ !66 = distinct !DILexicalBlock(scope: !64, column: 1)
+ !68 = !DILocation(line: 12, scope: !66)
+ !70 = distinct !DILexicalBlock(scope: !66, column: 1)
+ !71 = !DILocation(line: 13, scope: !70)
+name: main
+body: |
+ bb.0:
+ %1:_(s8) = G_CONSTANT i8 0, debug-location !68
+ %2:_(s32) = G_ANYEXT %1(s8), debug-location !68
+ $w2 = COPY %2(s32), debug-location !68
+ %3:_(s32) = G_CONSTANT i32 0, debug-location !71
+ $w0 = COPY %3(s32), debug-location !71
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