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[clang][CodeGen] Fix sub-optimal clang CodeGen for __atomic_test_and_set #160098

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Merged
merged 1 commit into from
Sep 26, 2025
Merged

[clang][CodeGen] Fix sub-optimal clang CodeGen for __atomic_test_and_set #160098

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3 changes: 2 additions & 1 deletion clang/lib/CodeGen/CGAtomic.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -734,7 +734,8 @@ static void EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, Address Dest,
CGF.emitAtomicRMWInst(llvm::AtomicRMWInst::Xchg, Ptr,
CGF.Builder.getInt8(1), Order, Scope, E);
RMWI->setVolatile(E->isVolatile());
llvm::Value *Result = CGF.Builder.CreateIsNotNull(RMWI, "tobool");
llvm::Value *Result = CGF.EmitToMemory(
CGF.Builder.CreateIsNotNull(RMWI, "tobool"), E->getType());
auto *I = CGF.Builder.CreateStore(Result, Dest);
CGF.addInstToCurrentSourceAtom(I, Result);
return;
Expand Down
45 changes: 30 additions & 15 deletions clang/test/CodeGen/atomic-test-and-set.c
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Original file line number Diff line number Diff line change
Expand Up @@ -81,7 +81,8 @@ void clear_dynamic(char *ptr, int order) {
// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 monotonic, align 1
// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT:%.*]] = zext i1 [[TOBOOL]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
// CHECK-NEXT: ret void
Expand All @@ -99,7 +100,8 @@ void test_and_set_relaxed(char *ptr) {
// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 acquire, align 1
// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT:%.*]] = zext i1 [[TOBOOL]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
// CHECK-NEXT: ret void
Expand All @@ -117,7 +119,8 @@ void test_and_set_consume(char *ptr) {
// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 acquire, align 1
// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT:%.*]] = zext i1 [[TOBOOL]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
// CHECK-NEXT: ret void
Expand All @@ -135,7 +138,8 @@ void test_and_set_acquire(char *ptr) {
// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 release, align 1
// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT:%.*]] = zext i1 [[TOBOOL]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
// CHECK-NEXT: ret void
Expand All @@ -153,7 +157,8 @@ void test_and_set_release(char *ptr) {
// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 acq_rel, align 1
// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT:%.*]] = zext i1 [[TOBOOL]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
// CHECK-NEXT: ret void
Expand All @@ -171,7 +176,8 @@ void test_and_set_acq_rel(char *ptr) {
// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 seq_cst, align 1
// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT:%.*]] = zext i1 [[TOBOOL]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
// CHECK-NEXT: ret void
Expand Down Expand Up @@ -200,27 +206,32 @@ void test_and_set_seq_cst(char *ptr) {
// CHECK: [[MONOTONIC]]:
// CHECK-NEXT: [[TMP2:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 monotonic, align 1
// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP2]], 0
// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT:%.*]] = zext i1 [[TOBOOL]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: br label %[[ATOMIC_CONTINUE:.*]]
// CHECK: [[ACQUIRE]]:
// CHECK-NEXT: [[TMP3:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 acquire, align 1
// CHECK-NEXT: [[TOBOOL1:%.*]] = icmp ne i8 [[TMP3]], 0
// CHECK-NEXT: store i1 [[TOBOOL1]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT1:%.*]] = zext i1 [[TOBOOL1]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT1]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: br label %[[ATOMIC_CONTINUE]]
// CHECK: [[RELEASE]]:
// CHECK-NEXT: [[TMP4:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 release, align 1
// CHECK-NEXT: [[TOBOOL2:%.*]] = icmp ne i8 [[TMP4]], 0
// CHECK-NEXT: store i1 [[TOBOOL2]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT2:%.*]] = zext i1 [[TOBOOL2]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT2]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: br label %[[ATOMIC_CONTINUE]]
// CHECK: [[ACQREL]]:
// CHECK-NEXT: [[TMP5:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 acq_rel, align 1
// CHECK-NEXT: [[TOBOOL3:%.*]] = icmp ne i8 [[TMP5]], 0
// CHECK-NEXT: store i1 [[TOBOOL3]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT3:%.*]] = zext i1 [[TOBOOL3]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT3]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: br label %[[ATOMIC_CONTINUE]]
// CHECK: [[SEQCST]]:
// CHECK-NEXT: [[TMP6:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 seq_cst, align 1
// CHECK-NEXT: [[TOBOOL4:%.*]] = icmp ne i8 [[TMP6]], 0
// CHECK-NEXT: store i1 [[TOBOOL4]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT4:%.*]] = zext i1 [[TOBOOL4]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT4]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: br label %[[ATOMIC_CONTINUE]]
// CHECK: [[ATOMIC_CONTINUE]]:
// CHECK-NEXT: [[TMP7:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
Expand All @@ -239,7 +250,8 @@ void test_and_set_dynamic(char *ptr, int order) {
// CHECK-NEXT: [[ARRAYDECAY:%.*]] = getelementptr inbounds [10 x i32], ptr [[X]], i64 0, i64 0
// CHECK-NEXT: [[TMP0:%.*]] = atomicrmw volatile xchg ptr [[ARRAYDECAY]], i8 1 seq_cst, align 4
// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP0]], 0
// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT:%.*]] = zext i1 [[TOBOOL]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TMP1:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP1]] to i1
// CHECK-NEXT: ret void
Expand Down Expand Up @@ -301,7 +313,8 @@ void clear_incomplete(struct incomplete *ptr) {
// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 monotonic, align 4
// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT:%.*]] = zext i1 [[TOBOOL]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
// CHECK-NEXT: ret void
Expand All @@ -318,7 +331,8 @@ void test_and_set_int(int *ptr) {
// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 monotonic, align 1
// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT:%.*]] = zext i1 [[TOBOOL]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
// CHECK-NEXT: ret void
Expand All @@ -335,7 +349,8 @@ void test_and_set_void(void *ptr) {
// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[PTR_ADDR]], align 8
// CHECK-NEXT: [[TMP1:%.*]] = atomicrmw xchg ptr [[TMP0]], i8 1 monotonic, align 1
// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[TMP1]], 0
// CHECK-NEXT: store i1 [[TOBOOL]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TOBOOL_ZEXT:%.*]] = zext i1 [[TOBOOL]] to i8
// CHECK-NEXT: store i8 [[TOBOOL_ZEXT]], ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[TMP2:%.*]] = load i8, ptr [[ATOMIC_TEMP]], align 1
// CHECK-NEXT: [[LOADEDV:%.*]] = trunc i8 [[TMP2]] to i1
// CHECK-NEXT: ret void
Expand Down
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