[KeyInstr][Clang] Atomic ops atoms #141624
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This patch is part of a stack that teaches Clang to generate Key Instructions metadata for C and C++. The feature is only functional in LLVM if LLVM is built with CMake flag LLVM_EXPERIMENTAL_KEY_INSTRUCTIONs. Eventually that flag will be removed. RFC: https://discourse.llvm.org/t/rfc-improving-is-stmt-placement-for-better-interactive-debugging/82668
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@llvm/pr-subscribers-clang Author: Orlando Cazalet-Hyams (OCHyams) ChangesThis patch is part of a stack that teaches Clang to generate Key Instructions metadata for C and C++. The feature is only functional in LLVM if LLVM is built with CMake flag LLVM_EXPERIMENTAL_KEY_INSTRUCTIONs. Eventually that flag will be removed. RFC: Full diff: https://github.com/llvm/llvm-project/pull/141624.diff 2 Files Affected:
diff --git a/clang/lib/CodeGen/CGAtomic.cpp b/clang/lib/CodeGen/CGAtomic.cpp
index 51f0799a792fd..9106c4cd8e139 100644
--- a/clang/lib/CodeGen/CGAtomic.cpp
+++ b/clang/lib/CodeGen/CGAtomic.cpp
@@ -411,7 +411,9 @@ static void emitAtomicCmpXchg(CodeGenFunction &CGF, AtomicExpr *E, bool IsWeak,
CGF.Builder.SetInsertPoint(StoreExpectedBB);
// Update the memory at Expected with Old's value.
- CGF.Builder.CreateStore(Old, Val1);
+ auto *I = CGF.Builder.CreateStore(Old, Val1);
+ CGF.addInstToCurrentSourceAtom(I, Old);
+
// Finally, branch to the exit point.
CGF.Builder.CreateBr(ContinueBB);
@@ -591,7 +593,8 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest,
Load->setAtomic(Order, Scope);
Load->setVolatile(E->isVolatile());
CGF.maybeAttachRangeForLoad(Load, E->getValueType(), E->getExprLoc());
- CGF.Builder.CreateStore(Load, Dest);
+ auto *I = CGF.Builder.CreateStore(Load, Dest);
+ CGF.addInstToCurrentSourceAtom(I, Load);
return;
}
@@ -606,6 +609,7 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest,
llvm::StoreInst *Store = CGF.Builder.CreateStore(LoadVal1, Ptr);
Store->setAtomic(Order, Scope);
Store->setVolatile(E->isVolatile());
+ CGF.addInstToCurrentSourceAtom(Store, LoadVal1);
return;
}
@@ -731,7 +735,8 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest,
CGF.Builder.getInt8(1), Order, Scope, E);
RMWI->setVolatile(E->isVolatile());
llvm::Value *Result = CGF.Builder.CreateIsNotNull(RMWI, "tobool");
- CGF.Builder.CreateStore(Result, Dest);
+ auto *I = CGF.Builder.CreateStore(Result, Dest);
+ CGF.addInstToCurrentSourceAtom(I, Result);
return;
}
@@ -740,6 +745,7 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest,
CGF.Builder.CreateStore(CGF.Builder.getInt8(0), Ptr);
Store->setAtomic(Order, Scope);
Store->setVolatile(E->isVolatile());
+ CGF.addInstToCurrentSourceAtom(Store, nullptr);
return;
}
}
@@ -762,7 +768,8 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest,
if (E->getOp() == AtomicExpr::AO__atomic_nand_fetch ||
E->getOp() == AtomicExpr::AO__scoped_atomic_nand_fetch)
Result = CGF.Builder.CreateNot(Result);
- CGF.Builder.CreateStore(Result, Dest);
+ auto *I = CGF.Builder.CreateStore(Result, Dest);
+ CGF.addInstToCurrentSourceAtom(I, Result);
}
// This function emits any expression (scalar, complex, or aggregate)
@@ -845,6 +852,8 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *Expr, Address Dest,
}
RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E) {
+ ApplyAtomGroup Grp(getDebugInfo());
+
QualType AtomicTy = E->getPtr()->getType()->getPointeeType();
QualType MemTy = AtomicTy;
if (const AtomicType *AT = AtomicTy->getAs<AtomicType>())
diff --git a/clang/test/DebugInfo/KeyInstructions/atomic.c b/clang/test/DebugInfo/KeyInstructions/atomic.c
new file mode 100644
index 0000000000000..da54e37714c3a
--- /dev/null
+++ b/clang/test/DebugInfo/KeyInstructions/atomic.c
@@ -0,0 +1,162 @@
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -gkey-instructions -x c++ -std=c++17 %s -debug-info-kind=line-tables-only -emit-llvm -o - -gno-column-info \
+// RUN: | FileCheck %s --implicit-check-not atomGroup --implicit-check-not atomRank
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -gkey-instructions -x c %s -debug-info-kind=line-tables-only -emit-llvm -o - -gno-column-info \
+// RUN: | FileCheck %s --implicit-check-not atomGroup --implicit-check-not atomRank
+
+// Check that atomic handling code gets Key Instruction annotations.
+
+_Atomic(unsigned int) x;
+unsigned int y;
+void fun() {
+ unsigned int r1 = __c11_atomic_fetch_add(&x,- 1, __ATOMIC_RELAXED);
+// CHECK: store i32 -1, ptr %.atomictmp, align 4, !dbg [[LINE11_G2R1:!.*]]
+// CHECK-NEXT: %0 = load i32, ptr %.atomictmp, align 4, !dbg [[LINE11:!.*]]
+// CHECK-NEXT: %1 = atomicrmw add ptr @x, i32 %0 monotonic, align 4, !dbg [[LINE11_G2R2:!.*]]
+// CHECK-NEXT: store i32 %1, ptr %atomic-temp, align 4, !dbg [[LINE11_G2R1]]
+// CHECK-NEXT: %2 = load i32, ptr %atomic-temp, align 4, !dbg [[LINE11_G1R2:!.*]]
+// CHECK-NEXT: store i32 %2, ptr %r1, align 4, !dbg [[LINE11_G1R1:!.*]]
+
+ unsigned int r2 = __c11_atomic_load(&x, __ATOMIC_RELAXED);
+// CHECK-NEXT: %3 = load atomic i32, ptr @x monotonic, align 4, !dbg [[LINE19_G4R2:!.*]]
+// CHECK-NEXT: store i32 %3, ptr %atomic-temp1, align 4, !dbg [[LINE19_G4R1:!.*]]
+// CHECK-NEXT: %4 = load i32, ptr %atomic-temp1, align 4, !dbg [[LINE19_G3R2:!.*]]
+// CHECK-NEXT: store i32 %4, ptr %r2, align 4, !dbg [[LINE19_G3R1:!.*]]
+
+ __c11_atomic_store(&x, 2, __ATOMIC_RELAXED);
+// CHECK-NEXT: store i32 2, ptr %.atomictmp2, align 4, !dbg [[LINE25_G5R1:!.*]]
+// CHECK-NEXT: %5 = load i32, ptr %.atomictmp2, align 4, !dbg [[LINE25_G5R2:!.*]]
+// CHECK-NEXT: store atomic i32 %5, ptr @x monotonic, align 4, !dbg [[LINE25_G5R1:!.*]]
+
+ int r3 = __atomic_test_and_set(&x, __ATOMIC_RELAXED);
+// CHECK-NEXT: %6 = atomicrmw xchg ptr @x, i8 1 monotonic, align 4, !dbg [[LINE30:!.*]]
+// CHECK-NEXT: %tobool = icmp ne i8 %6, 0, !dbg [[LINE30_G7R2:!.*]]
+// CHECK-NEXT: store i1 %tobool, ptr %atomic-temp3, align 1, !dbg [[LINE30_G7R1:!.*]]
+// CHECK-NEXT: %7 = load i8, ptr %atomic-temp3, align 1, !dbg [[LINE30_G6R4:!.*]]
+// CHECK-NEXT: %loadedv = trunc i8 %7 to i1, !dbg [[LINE30_G6R3:!.*]]
+// CHECK-NEXT: %conv = zext i1 %loadedv to i32, !dbg [[LINE30_G6R2:!.*]]
+// CHECK-NEXT: store i32 %conv, ptr %r3, align 4, !dbg [[LINE30_G6R1:!.*]]
+
+ __atomic_clear(&x, __ATOMIC_RELAXED);
+// CHECK-NEXT: store atomic i8 0, ptr @x monotonic, align 4, !dbg [[LINE39_G8R1:!.*]]
+
+ int r4 = __c11_atomic_exchange(&x, 2,__ATOMIC_RELAXED);
+// CHECK-NEXT: store i32 2, ptr %.atomictmp4, align 4, !dbg [[LINE42_G10R1:!.*]]
+// CHECK-NEXT: %8 = load i32, ptr %.atomictmp4, align 4, !dbg [[LINE42:!.*]]
+// CHECK-NEXT: %9 = atomicrmw xchg ptr @x, i32 %8 monotonic, align 4, !dbg [[LINE42_G10R2:!.*]]
+// CHECK-NEXT: store i32 %9, ptr %atomic-temp5, align 4, !dbg [[LINE42_G10R1:!.*]]
+// CHECK-NEXT: %10 = load i32, ptr %atomic-temp5, align 4, !dbg [[LINE42_G9R2:!.*]]
+// CHECK-NEXT: store i32 %10, ptr %r4, align 4, !dbg [[LINE42_G9R1:!.*]]
+
+ int r5 = __atomic_compare_exchange(&y, &y, &y, 0, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+// CHECK-NEXT: %11 = load i32, ptr @y, align 4, !dbg [[LINE50:!.*]]
+// CHECK-NEXT: %12 = load i32, ptr @y, align 4, !dbg [[LINE50]]
+// CHECK-NEXT: %13 = cmpxchg ptr @y, i32 %11, i32 %12 monotonic monotonic, align 4, !dbg [[LINE50]]
+// CHECK-NEXT: %14 = extractvalue { i32, i1 } %13, 0, !dbg [[LINE50_G12R2:!.*]]
+// CHECK-NEXT: %15 = extractvalue { i32, i1 } %13, 1, !dbg [[LINE50_G12R3:!.*]]
+// CHECK-NEXT: br i1 %15, label %cmpxchg.continue, label %cmpxchg.store_expected, !dbg [[LINE50]]
+// CHECK: cmpxchg.store_expected:
+// CHECK-NEXT: store i32 %14, ptr @y, align 4, !dbg [[LINE50_G12R1:!.*]]
+// CHECK-NEXT: br label %cmpxchg.continue, !dbg [[LINE50]]
+// CHECK: cmpxchg.continue:
+// CHECK-NEXT: %storedv = zext i1 %15 to i8, !dbg [[LINE50_G12R2]]
+// CHECK-NEXT: store i8 %storedv, ptr %cmpxchg.bool, align 1, !dbg [[LINE50_G12R1]]
+// CHECK-NEXT: %16 = load i8, ptr %cmpxchg.bool, align 1, !dbg [[LINE50_G11R4:!.*]]
+// CHECK-NEXT: %loadedv6 = trunc i8 %16 to i1, !dbg [[LINE50_G11R3:!.*]]
+// CHECK-NEXT: %conv7 = zext i1 %loadedv6 to i32, !dbg [[LINE50_G11R2:!.*]]
+// CHECK-NEXT: store i32 %conv7, ptr %r5, align 4, !dbg [[LINE50_G11R1:!.*]]
+
+ int r6 = __c11_atomic_compare_exchange_strong(&x, &y, 42, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+// CHECK-NEXT: store i32 42, ptr %.atomictmp8, align 4, !dbg [[LINE68_G14R1:!.*]]
+// CHECK-NEXT: %17 = load i32, ptr @y, align 4, !dbg [[LINE68:!.*]]
+// CHECK-NEXT: %18 = load i32, ptr %.atomictmp8, align 4, !dbg [[LINE68]]
+// CHECK-NEXT: %19 = cmpxchg ptr @x, i32 %17, i32 %18 monotonic monotonic, align 4, !dbg [[LINE68]]
+// CHECK-NEXT: %20 = extractvalue { i32, i1 } %19, 0, !dbg [[LINE68_G14R2:!.*]]
+// CHECK-NEXT: %21 = extractvalue { i32, i1 } %19, 1, !dbg [[LINE68_G14R3:!.*]]
+// CHECK-NEXT: br i1 %21, label %cmpxchg.continue11, label %cmpxchg.store_expected10, !dbg [[LINE68]]
+// CHECK: cmpxchg.store_expected10:
+// CHECK-NEXT: store i32 %20, ptr @y, align 4, !dbg [[LINE68_G14R1:!.*]]
+// CHECK-NEXT: br label %cmpxchg.continue11, !dbg [[LINE68]]
+// CHECK: cmpxchg.continue11:
+// CHECK-NEXT: %storedv12 = zext i1 %21 to i8, !dbg [[LINE68_G14R2]]
+// CHECK-NEXT: store i8 %storedv12, ptr %cmpxchg.bool9, align 1, !dbg [[LINE68_G14R1:!.*]]
+// CHECK-NEXT: %22 = load i8, ptr %cmpxchg.bool9, align 1, !dbg [[LINE68_G13R4:!.*]]
+// CHECK-NEXT: %loadedv13 = trunc i8 %22 to i1, !dbg [[LINE68_G13R3:!.*]]
+// CHECK-NEXT: %conv14 = zext i1 %loadedv13 to i32, !dbg [[LINE68_G13R2:!.*]]
+// CHECK-NEXT: store i32 %conv14, ptr %r6, align 4, !dbg [[LINE68_G13R1:!.*]]
+
+ int r7 = __c11_atomic_compare_exchange_weak(&x, &y, 43, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+// CHECK-NEXT: store i32 43, ptr %.atomictmp15, align 4, !dbg [[LINE87_G16R1:!.*]]
+// CHECK-NEXT: %23 = load i32, ptr @y, align 4, !dbg [[LINE87:!.*]]
+// CHECK-NEXT: %24 = load i32, ptr %.atomictmp15, align 4, !dbg [[LINE87]]
+// CHECK-NEXT: %25 = cmpxchg weak ptr @x, i32 %23, i32 %24 monotonic monotonic, align 4, !dbg [[LINE87]]
+// CHECK-NEXT: %26 = extractvalue { i32, i1 } %25, 0, !dbg [[LINE87_G16R2:!.*]]
+// CHECK-NEXT: %27 = extractvalue { i32, i1 } %25, 1, !dbg [[LINE87_G16R3:!.*]]
+// CHECK-NEXT: br i1 %27, label %cmpxchg.continue18, label %cmpxchg.store_expected17, !dbg [[LINE87]]
+// CHECK: cmpxchg.store_expected17:
+// CHECK-NEXT: store i32 %26, ptr @y, align 4, !dbg [[LINE87_G16R1]]
+// CHECK-NEXT: br label %cmpxchg.continue18, !dbg [[LINE87]]
+// CHECK: cmpxchg.continue18:
+// CHECK-NEXT: %storedv19 = zext i1 %27 to i8, !dbg [[LINE87_G16R2]]
+// CHECK-NEXT: store i8 %storedv19, ptr %cmpxchg.bool16, align 1, !dbg [[LINE87_G16R1]]
+// CHECK-NEXT: %28 = load i8, ptr %cmpxchg.bool16, align 1, !dbg [[LINE87_G15R4:!.*]]
+// CHECK-NEXT: %loadedv20 = trunc i8 %28 to i1, !dbg [[LINE87_G15R3:!.*]]
+// CHECK-NEXT: %conv21 = zext i1 %loadedv20 to i32, !dbg [[LINE87_G15R2:!.*]]
+// CHECK-NEXT: store i32 %conv21, ptr %r7, align 4, !dbg [[LINE87_G15R1:!.*]]
+}
+
+// CHECK: [[LINE11_G2R1]] = !DILocation(line: 11, scope: ![[#]], atomGroup: 2, atomRank: 1)
+// CHECK: [[LINE11]] = !DILocation(line: 11, scope: ![[#]])
+// CHECK: [[LINE11_G2R2]] = !DILocation(line: 11, scope: ![[#]], atomGroup: 2, atomRank: 2)
+// CHECK: [[LINE11_G1R2]] = !DILocation(line: 11, scope: ![[#]], atomGroup: 1, atomRank: 2)
+// CHECK: [[LINE11_G1R1]] = !DILocation(line: 11, scope: ![[#]], atomGroup: 1, atomRank: 1)
+
+// CHECK: [[LINE19_G4R2]] = !DILocation(line: 19, scope: ![[#]], atomGroup: 4, atomRank: 2)
+// CHECK: [[LINE19_G4R1]] = !DILocation(line: 19, scope: ![[#]], atomGroup: 4, atomRank: 1)
+// CHECK: [[LINE19_G3R2]] = !DILocation(line: 19, scope: ![[#]], atomGroup: 3, atomRank: 2)
+// CHECK: [[LINE19_G3R1]] = !DILocation(line: 19, scope: ![[#]], atomGroup: 3, atomRank: 1)
+
+// CHECK: [[LINE25_G5R1]] = !DILocation(line: 25, scope: ![[#]], atomGroup: 5, atomRank: 1)
+// CHECK: [[LINE25_G5R2]] = !DILocation(line: 25, scope: ![[#]], atomGroup: 5, atomRank: 2)
+
+// CHECK: [[LINE30]] = !DILocation(line: 30, scope: ![[#]])
+// CHECK: [[LINE30_G7R2]] = !DILocation(line: 30, scope: ![[#]], atomGroup: 7, atomRank: 2)
+// CHECK: [[LINE30_G7R1]] = !DILocation(line: 30, scope: ![[#]], atomGroup: 7, atomRank: 1)
+// CHECK: [[LINE30_G6R4]] = !DILocation(line: 30, scope: ![[#]], atomGroup: 6, atomRank: 4)
+// CHECK: [[LINE30_G6R3]] = !DILocation(line: 30, scope: ![[#]], atomGroup: 6, atomRank: 3)
+// CHECK: [[LINE30_G6R2]] = !DILocation(line: 30, scope: ![[#]], atomGroup: 6, atomRank: 2)
+// CHECK: [[LINE30_G6R1]] = !DILocation(line: 30, scope: ![[#]], atomGroup: 6, atomRank: 1)
+
+// CHECK: [[LINE39_G8R1]] = !DILocation(line: 39, scope: ![[#]], atomGroup: 8, atomRank: 1)
+
+// CHECK: [[LINE42_G10R1]] = !DILocation(line: 42, scope: ![[#]], atomGroup: 10, atomRank: 1)
+// CHECK: [[LINE42]] = !DILocation(line: 42, scope: ![[#]])
+// CHECK: [[LINE42_G10R2]] = !DILocation(line: 42, scope: ![[#]], atomGroup: 10, atomRank: 2)
+// CHECK: [[LINE42_G9R2]] = !DILocation(line: 42, scope: ![[#]], atomGroup: 9, atomRank: 2)
+// CHECK: [[LINE42_G9R1]] = !DILocation(line: 42, scope: ![[#]], atomGroup: 9, atomRank: 1)
+
+// CHECK: [[LINE50]] = !DILocation(line: 50, scope: ![[#]])
+// CHECK: [[LINE50_G12R2]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 12, atomRank: 2)
+// CHECK: [[LINE50_G12R3]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 12, atomRank: 3)
+// CHECK: [[LINE50_G12R1]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 12, atomRank: 1)
+// CHECK: [[LINE50_G11R4]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 11, atomRank: 4)
+// CHECK: [[LINE50_G11R3]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 11, atomRank: 3)
+// CHECK: [[LINE50_G11R2]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 11, atomRank: 2)
+// CHECK: [[LINE50_G11R1]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 11, atomRank: 1)
+
+// CHECK: [[LINE68_G14R1]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 14, atomRank: 1)
+// CHECK: [[LINE68]] = !DILocation(line: 68, scope: ![[#]])
+// CHECK: [[LINE68_G14R2]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 14, atomRank: 2)
+// CHECK: [[LINE68_G14R3]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 14, atomRank: 3)
+// CHECK: [[LINE68_G13R4]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 13, atomRank: 4)
+// CHECK: [[LINE68_G13R3]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 13, atomRank: 3)
+// CHECK: [[LINE68_G13R2]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 13, atomRank: 2)
+// CHECK: [[LINE68_G13R1]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 13, atomRank: 1)
+
+// CHECK: [[LINE87_G16R1]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 16, atomRank: 1)
+// CHECK: [[LINE87]] = !DILocation(line: 87, scope: ![[#]])
+// CHECK: [[LINE87_G16R2]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 16, atomRank: 2)
+// CHECK: [[LINE87_G16R3]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 16, atomRank: 3)
+// CHECK: [[LINE87_G15R4]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 15, atomRank: 4)
+// CHECK: [[LINE87_G15R3]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 15, atomRank: 3)
+// CHECK: [[LINE87_G15R2]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 15, atomRank: 2)
+// CHECK: [[LINE87_G15R1]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 15, atomRank: 1)
|
|
@llvm/pr-subscribers-clang-codegen Author: Orlando Cazalet-Hyams (OCHyams) ChangesThis patch is part of a stack that teaches Clang to generate Key Instructions metadata for C and C++. The feature is only functional in LLVM if LLVM is built with CMake flag LLVM_EXPERIMENTAL_KEY_INSTRUCTIONs. Eventually that flag will be removed. RFC: Full diff: https://github.com/llvm/llvm-project/pull/141624.diff 2 Files Affected:
diff --git a/clang/lib/CodeGen/CGAtomic.cpp b/clang/lib/CodeGen/CGAtomic.cpp
index 51f0799a792fd..9106c4cd8e139 100644
--- a/clang/lib/CodeGen/CGAtomic.cpp
+++ b/clang/lib/CodeGen/CGAtomic.cpp
@@ -411,7 +411,9 @@ static void emitAtomicCmpXchg(CodeGenFunction &CGF, AtomicExpr *E, bool IsWeak,
CGF.Builder.SetInsertPoint(StoreExpectedBB);
// Update the memory at Expected with Old's value.
- CGF.Builder.CreateStore(Old, Val1);
+ auto *I = CGF.Builder.CreateStore(Old, Val1);
+ CGF.addInstToCurrentSourceAtom(I, Old);
+
// Finally, branch to the exit point.
CGF.Builder.CreateBr(ContinueBB);
@@ -591,7 +593,8 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest,
Load->setAtomic(Order, Scope);
Load->setVolatile(E->isVolatile());
CGF.maybeAttachRangeForLoad(Load, E->getValueType(), E->getExprLoc());
- CGF.Builder.CreateStore(Load, Dest);
+ auto *I = CGF.Builder.CreateStore(Load, Dest);
+ CGF.addInstToCurrentSourceAtom(I, Load);
return;
}
@@ -606,6 +609,7 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest,
llvm::StoreInst *Store = CGF.Builder.CreateStore(LoadVal1, Ptr);
Store->setAtomic(Order, Scope);
Store->setVolatile(E->isVolatile());
+ CGF.addInstToCurrentSourceAtom(Store, LoadVal1);
return;
}
@@ -731,7 +735,8 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest,
CGF.Builder.getInt8(1), Order, Scope, E);
RMWI->setVolatile(E->isVolatile());
llvm::Value *Result = CGF.Builder.CreateIsNotNull(RMWI, "tobool");
- CGF.Builder.CreateStore(Result, Dest);
+ auto *I = CGF.Builder.CreateStore(Result, Dest);
+ CGF.addInstToCurrentSourceAtom(I, Result);
return;
}
@@ -740,6 +745,7 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest,
CGF.Builder.CreateStore(CGF.Builder.getInt8(0), Ptr);
Store->setAtomic(Order, Scope);
Store->setVolatile(E->isVolatile());
+ CGF.addInstToCurrentSourceAtom(Store, nullptr);
return;
}
}
@@ -762,7 +768,8 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest,
if (E->getOp() == AtomicExpr::AO__atomic_nand_fetch ||
E->getOp() == AtomicExpr::AO__scoped_atomic_nand_fetch)
Result = CGF.Builder.CreateNot(Result);
- CGF.Builder.CreateStore(Result, Dest);
+ auto *I = CGF.Builder.CreateStore(Result, Dest);
+ CGF.addInstToCurrentSourceAtom(I, Result);
}
// This function emits any expression (scalar, complex, or aggregate)
@@ -845,6 +852,8 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *Expr, Address Dest,
}
RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E) {
+ ApplyAtomGroup Grp(getDebugInfo());
+
QualType AtomicTy = E->getPtr()->getType()->getPointeeType();
QualType MemTy = AtomicTy;
if (const AtomicType *AT = AtomicTy->getAs<AtomicType>())
diff --git a/clang/test/DebugInfo/KeyInstructions/atomic.c b/clang/test/DebugInfo/KeyInstructions/atomic.c
new file mode 100644
index 0000000000000..da54e37714c3a
--- /dev/null
+++ b/clang/test/DebugInfo/KeyInstructions/atomic.c
@@ -0,0 +1,162 @@
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -gkey-instructions -x c++ -std=c++17 %s -debug-info-kind=line-tables-only -emit-llvm -o - -gno-column-info \
+// RUN: | FileCheck %s --implicit-check-not atomGroup --implicit-check-not atomRank
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -gkey-instructions -x c %s -debug-info-kind=line-tables-only -emit-llvm -o - -gno-column-info \
+// RUN: | FileCheck %s --implicit-check-not atomGroup --implicit-check-not atomRank
+
+// Check that atomic handling code gets Key Instruction annotations.
+
+_Atomic(unsigned int) x;
+unsigned int y;
+void fun() {
+ unsigned int r1 = __c11_atomic_fetch_add(&x,- 1, __ATOMIC_RELAXED);
+// CHECK: store i32 -1, ptr %.atomictmp, align 4, !dbg [[LINE11_G2R1:!.*]]
+// CHECK-NEXT: %0 = load i32, ptr %.atomictmp, align 4, !dbg [[LINE11:!.*]]
+// CHECK-NEXT: %1 = atomicrmw add ptr @x, i32 %0 monotonic, align 4, !dbg [[LINE11_G2R2:!.*]]
+// CHECK-NEXT: store i32 %1, ptr %atomic-temp, align 4, !dbg [[LINE11_G2R1]]
+// CHECK-NEXT: %2 = load i32, ptr %atomic-temp, align 4, !dbg [[LINE11_G1R2:!.*]]
+// CHECK-NEXT: store i32 %2, ptr %r1, align 4, !dbg [[LINE11_G1R1:!.*]]
+
+ unsigned int r2 = __c11_atomic_load(&x, __ATOMIC_RELAXED);
+// CHECK-NEXT: %3 = load atomic i32, ptr @x monotonic, align 4, !dbg [[LINE19_G4R2:!.*]]
+// CHECK-NEXT: store i32 %3, ptr %atomic-temp1, align 4, !dbg [[LINE19_G4R1:!.*]]
+// CHECK-NEXT: %4 = load i32, ptr %atomic-temp1, align 4, !dbg [[LINE19_G3R2:!.*]]
+// CHECK-NEXT: store i32 %4, ptr %r2, align 4, !dbg [[LINE19_G3R1:!.*]]
+
+ __c11_atomic_store(&x, 2, __ATOMIC_RELAXED);
+// CHECK-NEXT: store i32 2, ptr %.atomictmp2, align 4, !dbg [[LINE25_G5R1:!.*]]
+// CHECK-NEXT: %5 = load i32, ptr %.atomictmp2, align 4, !dbg [[LINE25_G5R2:!.*]]
+// CHECK-NEXT: store atomic i32 %5, ptr @x monotonic, align 4, !dbg [[LINE25_G5R1:!.*]]
+
+ int r3 = __atomic_test_and_set(&x, __ATOMIC_RELAXED);
+// CHECK-NEXT: %6 = atomicrmw xchg ptr @x, i8 1 monotonic, align 4, !dbg [[LINE30:!.*]]
+// CHECK-NEXT: %tobool = icmp ne i8 %6, 0, !dbg [[LINE30_G7R2:!.*]]
+// CHECK-NEXT: store i1 %tobool, ptr %atomic-temp3, align 1, !dbg [[LINE30_G7R1:!.*]]
+// CHECK-NEXT: %7 = load i8, ptr %atomic-temp3, align 1, !dbg [[LINE30_G6R4:!.*]]
+// CHECK-NEXT: %loadedv = trunc i8 %7 to i1, !dbg [[LINE30_G6R3:!.*]]
+// CHECK-NEXT: %conv = zext i1 %loadedv to i32, !dbg [[LINE30_G6R2:!.*]]
+// CHECK-NEXT: store i32 %conv, ptr %r3, align 4, !dbg [[LINE30_G6R1:!.*]]
+
+ __atomic_clear(&x, __ATOMIC_RELAXED);
+// CHECK-NEXT: store atomic i8 0, ptr @x monotonic, align 4, !dbg [[LINE39_G8R1:!.*]]
+
+ int r4 = __c11_atomic_exchange(&x, 2,__ATOMIC_RELAXED);
+// CHECK-NEXT: store i32 2, ptr %.atomictmp4, align 4, !dbg [[LINE42_G10R1:!.*]]
+// CHECK-NEXT: %8 = load i32, ptr %.atomictmp4, align 4, !dbg [[LINE42:!.*]]
+// CHECK-NEXT: %9 = atomicrmw xchg ptr @x, i32 %8 monotonic, align 4, !dbg [[LINE42_G10R2:!.*]]
+// CHECK-NEXT: store i32 %9, ptr %atomic-temp5, align 4, !dbg [[LINE42_G10R1:!.*]]
+// CHECK-NEXT: %10 = load i32, ptr %atomic-temp5, align 4, !dbg [[LINE42_G9R2:!.*]]
+// CHECK-NEXT: store i32 %10, ptr %r4, align 4, !dbg [[LINE42_G9R1:!.*]]
+
+ int r5 = __atomic_compare_exchange(&y, &y, &y, 0, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+// CHECK-NEXT: %11 = load i32, ptr @y, align 4, !dbg [[LINE50:!.*]]
+// CHECK-NEXT: %12 = load i32, ptr @y, align 4, !dbg [[LINE50]]
+// CHECK-NEXT: %13 = cmpxchg ptr @y, i32 %11, i32 %12 monotonic monotonic, align 4, !dbg [[LINE50]]
+// CHECK-NEXT: %14 = extractvalue { i32, i1 } %13, 0, !dbg [[LINE50_G12R2:!.*]]
+// CHECK-NEXT: %15 = extractvalue { i32, i1 } %13, 1, !dbg [[LINE50_G12R3:!.*]]
+// CHECK-NEXT: br i1 %15, label %cmpxchg.continue, label %cmpxchg.store_expected, !dbg [[LINE50]]
+// CHECK: cmpxchg.store_expected:
+// CHECK-NEXT: store i32 %14, ptr @y, align 4, !dbg [[LINE50_G12R1:!.*]]
+// CHECK-NEXT: br label %cmpxchg.continue, !dbg [[LINE50]]
+// CHECK: cmpxchg.continue:
+// CHECK-NEXT: %storedv = zext i1 %15 to i8, !dbg [[LINE50_G12R2]]
+// CHECK-NEXT: store i8 %storedv, ptr %cmpxchg.bool, align 1, !dbg [[LINE50_G12R1]]
+// CHECK-NEXT: %16 = load i8, ptr %cmpxchg.bool, align 1, !dbg [[LINE50_G11R4:!.*]]
+// CHECK-NEXT: %loadedv6 = trunc i8 %16 to i1, !dbg [[LINE50_G11R3:!.*]]
+// CHECK-NEXT: %conv7 = zext i1 %loadedv6 to i32, !dbg [[LINE50_G11R2:!.*]]
+// CHECK-NEXT: store i32 %conv7, ptr %r5, align 4, !dbg [[LINE50_G11R1:!.*]]
+
+ int r6 = __c11_atomic_compare_exchange_strong(&x, &y, 42, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+// CHECK-NEXT: store i32 42, ptr %.atomictmp8, align 4, !dbg [[LINE68_G14R1:!.*]]
+// CHECK-NEXT: %17 = load i32, ptr @y, align 4, !dbg [[LINE68:!.*]]
+// CHECK-NEXT: %18 = load i32, ptr %.atomictmp8, align 4, !dbg [[LINE68]]
+// CHECK-NEXT: %19 = cmpxchg ptr @x, i32 %17, i32 %18 monotonic monotonic, align 4, !dbg [[LINE68]]
+// CHECK-NEXT: %20 = extractvalue { i32, i1 } %19, 0, !dbg [[LINE68_G14R2:!.*]]
+// CHECK-NEXT: %21 = extractvalue { i32, i1 } %19, 1, !dbg [[LINE68_G14R3:!.*]]
+// CHECK-NEXT: br i1 %21, label %cmpxchg.continue11, label %cmpxchg.store_expected10, !dbg [[LINE68]]
+// CHECK: cmpxchg.store_expected10:
+// CHECK-NEXT: store i32 %20, ptr @y, align 4, !dbg [[LINE68_G14R1:!.*]]
+// CHECK-NEXT: br label %cmpxchg.continue11, !dbg [[LINE68]]
+// CHECK: cmpxchg.continue11:
+// CHECK-NEXT: %storedv12 = zext i1 %21 to i8, !dbg [[LINE68_G14R2]]
+// CHECK-NEXT: store i8 %storedv12, ptr %cmpxchg.bool9, align 1, !dbg [[LINE68_G14R1:!.*]]
+// CHECK-NEXT: %22 = load i8, ptr %cmpxchg.bool9, align 1, !dbg [[LINE68_G13R4:!.*]]
+// CHECK-NEXT: %loadedv13 = trunc i8 %22 to i1, !dbg [[LINE68_G13R3:!.*]]
+// CHECK-NEXT: %conv14 = zext i1 %loadedv13 to i32, !dbg [[LINE68_G13R2:!.*]]
+// CHECK-NEXT: store i32 %conv14, ptr %r6, align 4, !dbg [[LINE68_G13R1:!.*]]
+
+ int r7 = __c11_atomic_compare_exchange_weak(&x, &y, 43, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
+// CHECK-NEXT: store i32 43, ptr %.atomictmp15, align 4, !dbg [[LINE87_G16R1:!.*]]
+// CHECK-NEXT: %23 = load i32, ptr @y, align 4, !dbg [[LINE87:!.*]]
+// CHECK-NEXT: %24 = load i32, ptr %.atomictmp15, align 4, !dbg [[LINE87]]
+// CHECK-NEXT: %25 = cmpxchg weak ptr @x, i32 %23, i32 %24 monotonic monotonic, align 4, !dbg [[LINE87]]
+// CHECK-NEXT: %26 = extractvalue { i32, i1 } %25, 0, !dbg [[LINE87_G16R2:!.*]]
+// CHECK-NEXT: %27 = extractvalue { i32, i1 } %25, 1, !dbg [[LINE87_G16R3:!.*]]
+// CHECK-NEXT: br i1 %27, label %cmpxchg.continue18, label %cmpxchg.store_expected17, !dbg [[LINE87]]
+// CHECK: cmpxchg.store_expected17:
+// CHECK-NEXT: store i32 %26, ptr @y, align 4, !dbg [[LINE87_G16R1]]
+// CHECK-NEXT: br label %cmpxchg.continue18, !dbg [[LINE87]]
+// CHECK: cmpxchg.continue18:
+// CHECK-NEXT: %storedv19 = zext i1 %27 to i8, !dbg [[LINE87_G16R2]]
+// CHECK-NEXT: store i8 %storedv19, ptr %cmpxchg.bool16, align 1, !dbg [[LINE87_G16R1]]
+// CHECK-NEXT: %28 = load i8, ptr %cmpxchg.bool16, align 1, !dbg [[LINE87_G15R4:!.*]]
+// CHECK-NEXT: %loadedv20 = trunc i8 %28 to i1, !dbg [[LINE87_G15R3:!.*]]
+// CHECK-NEXT: %conv21 = zext i1 %loadedv20 to i32, !dbg [[LINE87_G15R2:!.*]]
+// CHECK-NEXT: store i32 %conv21, ptr %r7, align 4, !dbg [[LINE87_G15R1:!.*]]
+}
+
+// CHECK: [[LINE11_G2R1]] = !DILocation(line: 11, scope: ![[#]], atomGroup: 2, atomRank: 1)
+// CHECK: [[LINE11]] = !DILocation(line: 11, scope: ![[#]])
+// CHECK: [[LINE11_G2R2]] = !DILocation(line: 11, scope: ![[#]], atomGroup: 2, atomRank: 2)
+// CHECK: [[LINE11_G1R2]] = !DILocation(line: 11, scope: ![[#]], atomGroup: 1, atomRank: 2)
+// CHECK: [[LINE11_G1R1]] = !DILocation(line: 11, scope: ![[#]], atomGroup: 1, atomRank: 1)
+
+// CHECK: [[LINE19_G4R2]] = !DILocation(line: 19, scope: ![[#]], atomGroup: 4, atomRank: 2)
+// CHECK: [[LINE19_G4R1]] = !DILocation(line: 19, scope: ![[#]], atomGroup: 4, atomRank: 1)
+// CHECK: [[LINE19_G3R2]] = !DILocation(line: 19, scope: ![[#]], atomGroup: 3, atomRank: 2)
+// CHECK: [[LINE19_G3R1]] = !DILocation(line: 19, scope: ![[#]], atomGroup: 3, atomRank: 1)
+
+// CHECK: [[LINE25_G5R1]] = !DILocation(line: 25, scope: ![[#]], atomGroup: 5, atomRank: 1)
+// CHECK: [[LINE25_G5R2]] = !DILocation(line: 25, scope: ![[#]], atomGroup: 5, atomRank: 2)
+
+// CHECK: [[LINE30]] = !DILocation(line: 30, scope: ![[#]])
+// CHECK: [[LINE30_G7R2]] = !DILocation(line: 30, scope: ![[#]], atomGroup: 7, atomRank: 2)
+// CHECK: [[LINE30_G7R1]] = !DILocation(line: 30, scope: ![[#]], atomGroup: 7, atomRank: 1)
+// CHECK: [[LINE30_G6R4]] = !DILocation(line: 30, scope: ![[#]], atomGroup: 6, atomRank: 4)
+// CHECK: [[LINE30_G6R3]] = !DILocation(line: 30, scope: ![[#]], atomGroup: 6, atomRank: 3)
+// CHECK: [[LINE30_G6R2]] = !DILocation(line: 30, scope: ![[#]], atomGroup: 6, atomRank: 2)
+// CHECK: [[LINE30_G6R1]] = !DILocation(line: 30, scope: ![[#]], atomGroup: 6, atomRank: 1)
+
+// CHECK: [[LINE39_G8R1]] = !DILocation(line: 39, scope: ![[#]], atomGroup: 8, atomRank: 1)
+
+// CHECK: [[LINE42_G10R1]] = !DILocation(line: 42, scope: ![[#]], atomGroup: 10, atomRank: 1)
+// CHECK: [[LINE42]] = !DILocation(line: 42, scope: ![[#]])
+// CHECK: [[LINE42_G10R2]] = !DILocation(line: 42, scope: ![[#]], atomGroup: 10, atomRank: 2)
+// CHECK: [[LINE42_G9R2]] = !DILocation(line: 42, scope: ![[#]], atomGroup: 9, atomRank: 2)
+// CHECK: [[LINE42_G9R1]] = !DILocation(line: 42, scope: ![[#]], atomGroup: 9, atomRank: 1)
+
+// CHECK: [[LINE50]] = !DILocation(line: 50, scope: ![[#]])
+// CHECK: [[LINE50_G12R2]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 12, atomRank: 2)
+// CHECK: [[LINE50_G12R3]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 12, atomRank: 3)
+// CHECK: [[LINE50_G12R1]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 12, atomRank: 1)
+// CHECK: [[LINE50_G11R4]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 11, atomRank: 4)
+// CHECK: [[LINE50_G11R3]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 11, atomRank: 3)
+// CHECK: [[LINE50_G11R2]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 11, atomRank: 2)
+// CHECK: [[LINE50_G11R1]] = !DILocation(line: 50, scope: ![[#]], atomGroup: 11, atomRank: 1)
+
+// CHECK: [[LINE68_G14R1]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 14, atomRank: 1)
+// CHECK: [[LINE68]] = !DILocation(line: 68, scope: ![[#]])
+// CHECK: [[LINE68_G14R2]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 14, atomRank: 2)
+// CHECK: [[LINE68_G14R3]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 14, atomRank: 3)
+// CHECK: [[LINE68_G13R4]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 13, atomRank: 4)
+// CHECK: [[LINE68_G13R3]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 13, atomRank: 3)
+// CHECK: [[LINE68_G13R2]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 13, atomRank: 2)
+// CHECK: [[LINE68_G13R1]] = !DILocation(line: 68, scope: ![[#]], atomGroup: 13, atomRank: 1)
+
+// CHECK: [[LINE87_G16R1]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 16, atomRank: 1)
+// CHECK: [[LINE87]] = !DILocation(line: 87, scope: ![[#]])
+// CHECK: [[LINE87_G16R2]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 16, atomRank: 2)
+// CHECK: [[LINE87_G16R3]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 16, atomRank: 3)
+// CHECK: [[LINE87_G15R4]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 15, atomRank: 4)
+// CHECK: [[LINE87_G15R3]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 15, atomRank: 3)
+// CHECK: [[LINE87_G15R2]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 15, atomRank: 2)
+// CHECK: [[LINE87_G15R1]] = !DILocation(line: 87, scope: ![[#]], atomGroup: 15, atomRank: 1)
|
|
Ping |
jmorse
approved these changes
Jun 24, 2025
| // CHECK: store i32 -1, ptr %.atomictmp, align 4, !dbg [[LINE11_G2R1:!.*]] | ||
| // CHECK-NEXT: %0 = load i32, ptr %.atomictmp, align 4, !dbg [[LINE11:!.*]] | ||
| // CHECK-NEXT: %1 = atomicrmw add ptr @x, i32 %0 monotonic, align 4, !dbg [[LINE11_G2R2:!.*]] | ||
| // CHECK-NEXT: store i32 %1, ptr %atomic-temp, align 4, !dbg [[LINE11_G2R1]] |
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So it's deliberate + desirable that both this and the earlier store of -1 are group-two-rank-one? (I suppose the buoy-based KIs will float the breakpoint upwards)
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Yeah it's deliberate. Possibly could be argued that the first store is "setup" and doesn't need to be key at all. I don't have a strong opinion either way, both should produce identical output if the instructions remain grouped like this (as you point out, due to the Buoys). The difference is if they split up over multiple blocks; the current impl has you stepping on the line twice, whereas alternative impls may have you step on this one.
Do you have a strong opinion?
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I've no strong opinion; I suspect due to the stricter rules on atomic regions we wouldn't see this split over multiple blocks, but I wouldn't want to be quoted on that.
DrSergei
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This patch is part of a stack that teaches Clang to generate Key Instructions metadata for C and C++. The feature is only functional in LLVM if LLVM is built with CMake flag LLVM_EXPERIMENTAL_KEY_INSTRUCTIONs. Eventually that flag will be removed. RFC: https://discourse.llvm.org/t/rfc-improving-is-stmt-placement-for-better-interactive-debugging/82668
DrSergei
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Jun 24, 2025
Fixup test added in llvm#141624 (ddecfa6).
anthonyhatran
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Jun 26, 2025
This patch is part of a stack that teaches Clang to generate Key Instructions metadata for C and C++. The feature is only functional in LLVM if LLVM is built with CMake flag LLVM_EXPERIMENTAL_KEY_INSTRUCTIONs. Eventually that flag will be removed. RFC: https://discourse.llvm.org/t/rfc-improving-is-stmt-placement-for-better-interactive-debugging/82668
anthonyhatran
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Jun 26, 2025
Fixup test added in llvm#141624 (ddecfa6).
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This patch is part of a stack that teaches Clang to generate Key Instructions metadata for C and C++.
The feature is only functional in LLVM if LLVM is built with CMake flag LLVM_EXPERIMENTAL_KEY_INSTRUCTIONs. Eventually that flag will be removed.
RFC:
https://discourse.llvm.org/t/rfc-improving-is-stmt-placement-for-better-interactive-debugging/82668