https://github.com/OCHyams updated https://github.com/llvm/llvm-project/pull/134647
>From 240476a6bcc82d37825aeea626fccf58590495a8 Mon Sep 17 00:00:00 2001 From: Orlando Cazalet-Hyams <orlando.hy...@sony.com> Date: Thu, 3 Apr 2025 19:46:01 +0100 Subject: [PATCH 1/2] [KeyInstr][Clang] For range stmt atoms This patch is part of a stack that teaches Clang to generate Key Instructions metadata for C and C++. The Key Instructions project is introduced, including a "quick summary" section at the top which adds context for this PR, here: https://discourse.llvm.org/t/rfc-improving-is-stmt-placement-for-better-interactive-debugging/82668 The feature is only functional in LLVM if LLVM is built with CMake flag LLVM_EXPERIMENTAL_KEY_INSTRUCTIONs. Eventually that flag will be removed. The Clang-side work is demoed here: https://github.com/llvm/llvm-project/pull/130943 --- clang/lib/CodeGen/CGStmt.cpp | 13 +++- .../DebugInfo/KeyInstructions/for-range.cpp | 72 +++++++++++++++++++ 2 files changed, 84 insertions(+), 1 deletion(-) create mode 100644 clang/test/DebugInfo/KeyInstructions/for-range.cpp diff --git a/clang/lib/CodeGen/CGStmt.cpp b/clang/lib/CodeGen/CGStmt.cpp index 65b71c39d86c4..9292be24fc12e 100644 --- a/clang/lib/CodeGen/CGStmt.cpp +++ b/clang/lib/CodeGen/CGStmt.cpp @@ -1477,7 +1477,14 @@ CodeGenFunction::EmitCXXForRangeStmt(const CXXForRangeStmt &S, if (!Weights && CGM.getCodeGenOpts().OptimizationLevel) BoolCondVal = emitCondLikelihoodViaExpectIntrinsic( BoolCondVal, Stmt::getLikelihood(S.getBody())); - Builder.CreateCondBr(BoolCondVal, ForBody, ExitBlock, Weights); + auto *I = Builder.CreateCondBr(BoolCondVal, ForBody, ExitBlock, Weights); + // Key Instructions: Emit the condition and branch as separate atoms to + // match existing loop stepping behaviour. FIXME: We could have the branch as + // the backup location for the condition, which would probably be a better + // experience. + if (auto *I = dyn_cast<llvm::Instruction>(BoolCondVal)) + addInstToNewSourceAtom(I, nullptr); + addInstToNewSourceAtom(I, nullptr); if (ExitBlock != LoopExit.getBlock()) { EmitBlock(ExitBlock); @@ -1526,6 +1533,10 @@ CodeGenFunction::EmitCXXForRangeStmt(const CXXForRangeStmt &S, if (CGM.shouldEmitConvergenceTokens()) ConvergenceTokenStack.pop_back(); + + // We want the for closing brace to be step-able on to match existing + // behaviour. + addInstToNewSourceAtom(ForBody->getTerminator(), nullptr); } void CodeGenFunction::EmitReturnOfRValue(RValue RV, QualType Ty) { diff --git a/clang/test/DebugInfo/KeyInstructions/for-range.cpp b/clang/test/DebugInfo/KeyInstructions/for-range.cpp new file mode 100644 index 0000000000000..be71d9fbfb581 --- /dev/null +++ b/clang/test/DebugInfo/KeyInstructions/for-range.cpp @@ -0,0 +1,72 @@ +// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 5 +// RUN: %clang -gkey-instructions %s -gmlt -S -emit-llvm -o - \ +// RUN: | FileCheck %s --implicit-check-not atomGroup --implicit-check-not atomRank + +// Perennial quesiton: should the inc be its own source atom or not +// (currently it is). + +// FIXME: See do.c and while.c regarding cmp and cond br groups. + +// The stores in the setup (stores to __RANGE1, __BEGIN1, __END1) are all +// marked as Key. Unclear whether that's desirable. Keep for now as that's +// least risky. + +// Check the conditional branch (and the condition) in FOR_COND and +// unconditional branch in FOR_BODY are Key Instructions. + +struct Range { + int *begin(); + int *end(); +} r; + +// CHECK-LABEL: define dso_local void @_Z1av( +// CHECK-SAME: ) #[[ATTR0:[0-9]+]] !dbg [[DBG10:![0-9]+]] { +// CHECK-NEXT: [[ENTRY:.*:]] +// CHECK-NEXT: [[__RANGE1:%.*]] = alloca ptr, align 8 +// CHECK-NEXT: [[__BEGIN1:%.*]] = alloca ptr, align 8 +// CHECK-NEXT: [[__END1:%.*]] = alloca ptr, align 8 +// CHECK-NEXT: [[I:%.*]] = alloca i32, align 4 +// CHECK-NEXT: store ptr @r, ptr [[__RANGE1]], align 8, !dbg [[DBG14:![0-9]+]] +// CHECK-NEXT: [[CALL:%.*]] = call noundef ptr @_ZN5Range5beginEv(ptr noundef nonnull align 1 dereferenceable(1) @r), !dbg [[DBG15:![0-9]+]] +// CHECK-NEXT: store ptr [[CALL]], ptr [[__BEGIN1]], align 8, !dbg [[DBG16:![0-9]+]] +// CHECK-NEXT: [[CALL1:%.*]] = call noundef ptr @_ZN5Range3endEv(ptr noundef nonnull align 1 dereferenceable(1) @r), !dbg [[DBG17:![0-9]+]] +// CHECK-NEXT: store ptr [[CALL1]], ptr [[__END1]], align 8, !dbg [[DBG18:![0-9]+]] +// CHECK-NEXT: br label %[[FOR_COND:.*]], !dbg [[DBG19:![0-9]+]] +// CHECK: [[FOR_COND]]: +// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[__BEGIN1]], align 8, !dbg [[DBG19]] +// CHECK-NEXT: [[TMP1:%.*]] = load ptr, ptr [[__END1]], align 8, !dbg [[DBG19]] +// CHECK-NEXT: [[CMP:%.*]] = icmp ne ptr [[TMP0]], [[TMP1]], !dbg [[DBG20:![0-9]+]] +// CHECK-NEXT: br i1 [[CMP]], label %[[FOR_BODY:.*]], label %[[FOR_END:.*]], !dbg [[DBG21:![0-9]+]] +// CHECK: [[FOR_BODY]]: +// CHECK-NEXT: [[TMP2:%.*]] = load ptr, ptr [[__BEGIN1]], align 8, !dbg [[DBG19]] +// CHECK-NEXT: [[TMP3:%.*]] = load i32, ptr [[TMP2]], align 4, !dbg [[DBG22:![0-9]+]] +// CHECK-NEXT: store i32 [[TMP3]], ptr [[I]], align 4, !dbg [[DBG23:![0-9]+]] +// CHECK-NEXT: br label %[[FOR_INC:.*]], !dbg [[DBG24:![0-9]+]] +// CHECK: [[FOR_INC]]: +// CHECK-NEXT: [[TMP4:%.*]] = load ptr, ptr [[__BEGIN1]], align 8, !dbg [[DBG19]] +// CHECK-NEXT: [[INCDEC_PTR:%.*]] = getelementptr inbounds nuw i32, ptr [[TMP4]], i32 1, !dbg [[DBG25:![0-9]+]] +// CHECK-NEXT: store ptr [[INCDEC_PTR]], ptr [[__BEGIN1]], align 8, !dbg [[DBG26:![0-9]+]] +// CHECK-NEXT: br label %[[FOR_COND]], !dbg [[DBG19]], !llvm.loop +// CHECK: [[FOR_END]]: +// CHECK-NEXT: ret void, !dbg [[DBG30:![0-9]+]] +// +void a() { + for (int i: r) + ; +} +//. +// CHECK: [[DBG14]] = !DILocation({{.*}}, atomGroup: 1, atomRank: 1) +// CHECK: [[DBG15]] = !DILocation({{.*}}, atomGroup: 2, atomRank: 2) +// CHECK: [[DBG16]] = !DILocation({{.*}}, atomGroup: 2, atomRank: 1) +// CHECK: [[DBG17]] = !DILocation({{.*}}, atomGroup: 3, atomRank: 2) +// CHECK: [[DBG18]] = !DILocation({{.*}}, atomGroup: 3, atomRank: 1) +// CHECK: [[DBG19]] = !DILocation({{.*}}) +// CHECK: [[DBG20]] = !DILocation({{.*}}, atomGroup: 4, atomRank: 1) +// CHECK: [[DBG21]] = !DILocation({{.*}}, atomGroup: 5, atomRank: 1) +// CHECK: [[DBG22]] = !DILocation({{.*}}, atomGroup: 6, atomRank: 2) +// CHECK: [[DBG23]] = !DILocation({{.*}}, atomGroup: 6, atomRank: 1) +// CHECK: [[DBG24]] = !DILocation({{.*}} atomGroup: 8, atomRank: 1) +// CHECK: [[DBG25]] = !DILocation({{.*}}, atomGroup: 7, atomRank: 2) +// CHECK: [[DBG26]] = !DILocation({{.*}}, atomGroup: 7, atomRank: 1) +// CHECK: [[DBG30]] = !DILocation({{.*}}) +//. >From bd77fcbccc223d58becc4364276b8fb92aa56a3e Mon Sep 17 00:00:00 2001 From: Orlando Cazalet-Hyams <orlando.hy...@sony.com> Date: Wed, 21 May 2025 15:52:22 +0100 Subject: [PATCH 2/2] cc1 + nits --- clang/lib/CodeGen/CGStmt.cpp | 2 +- clang/test/DebugInfo/KeyInstructions/for-range.cpp | 3 +-- 2 files changed, 2 insertions(+), 3 deletions(-) diff --git a/clang/lib/CodeGen/CGStmt.cpp b/clang/lib/CodeGen/CGStmt.cpp index 9292be24fc12e..2696bc9cc379b 100644 --- a/clang/lib/CodeGen/CGStmt.cpp +++ b/clang/lib/CodeGen/CGStmt.cpp @@ -1535,7 +1535,7 @@ CodeGenFunction::EmitCXXForRangeStmt(const CXXForRangeStmt &S, ConvergenceTokenStack.pop_back(); // We want the for closing brace to be step-able on to match existing - // behaviour. + // behaviour. addInstToNewSourceAtom(ForBody->getTerminator(), nullptr); } diff --git a/clang/test/DebugInfo/KeyInstructions/for-range.cpp b/clang/test/DebugInfo/KeyInstructions/for-range.cpp index be71d9fbfb581..3898942622e89 100644 --- a/clang/test/DebugInfo/KeyInstructions/for-range.cpp +++ b/clang/test/DebugInfo/KeyInstructions/for-range.cpp @@ -1,5 +1,4 @@ -// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 5 -// RUN: %clang -gkey-instructions %s -gmlt -S -emit-llvm -o - \ +// RUN: %clang_cc1 -gkey-instructions %s -debug-info-kind=line-tables-only -emit-llvm -o - \ // RUN: | FileCheck %s --implicit-check-not atomGroup --implicit-check-not atomRank // Perennial quesiton: should the inc be its own source atom or not _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
