[clang][AMDGPU] Fix -ast-print crash on expanded predicate builtins#199963
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@llvm/pr-subscribers-clang @llvm/pr-subscribers-backend-amdgpu Author: lijinpei-amd ChangesExpandAMDGPUPredicateBuiltIn synthesized an IntegerLiteral typed _Bool/bool — a shape no other producer creates, and one that StmtPrinter::VisitIntegerLiteral has no case for. -ast-print on the resulting if-condition hit llvm_unreachable. Emit the canonical boolean literal instead:
In the C case this matches what <stdbool.h>'s true/false macros expand to. Fixes #199563 Full diff: https://github.com/llvm/llvm-project/pull/199963.diff 2 Files Affected:
diff --git a/clang/lib/Sema/SemaAMDGPU.cpp b/clang/lib/Sema/SemaAMDGPU.cpp
index 1d2b3898c92d6..3f0ce5b3a080b 100644
--- a/clang/lib/Sema/SemaAMDGPU.cpp
+++ b/clang/lib/Sema/SemaAMDGPU.cpp
@@ -760,14 +760,21 @@ Expr *SemaAMDGPU::ExpandAMDGPUPredicateBuiltIn(Expr *E) {
CallExpr *CE = cast<CallExpr>(E->IgnoreParens());
ASTContext &Ctx = getASTContext();
QualType BoolTy = Ctx.getLogicalOperationType();
- llvm::APInt False = llvm::APInt::getZero(Ctx.getIntWidth(BoolTy));
- llvm::APInt True = llvm::APInt::getAllOnes(Ctx.getIntWidth(BoolTy));
SourceLocation Loc = CE->getExprLoc();
+ // A plain IntegerLiteral whose type is _Bool/bool is not a shape any other
+ // clang producer creates, and consumers (e.g. StmtPrinter) assume it cannot
+ // occur — see issue #199563.
+ auto MakePredicateLiteral = [&](bool Val) -> Expr * {
+ if (Ctx.getLangOpts().Bool)
+ return SemaRef
+ .ActOnCXXBoolLiteral(Loc, Val ? tok::kw_true : tok::kw_false)
+ .get();
+ return SemaRef.ActOnIntegerConstant(Loc, Val ? 1 : 0).get();
+ };
+
if (!CE->getBuiltinCallee())
- return *ExpandedPredicates
- .insert(IntegerLiteral::Create(Ctx, False, BoolTy, Loc))
- .first;
+ return *ExpandedPredicates.insert(MakePredicateLiteral(false)).first;
bool P = false;
unsigned BI = CE->getBuiltinCallee();
@@ -824,10 +831,7 @@ Expr *SemaAMDGPU::ExpandAMDGPUPredicateBuiltIn(Expr *E) {
P = Builtin::evaluateRequiredTargetFeatures(RF, CF);
}
- return *ExpandedPredicates
- .insert(
- IntegerLiteral::Create(Ctx, P ? True : False, BoolTy, Loc))
- .first;
+ return *ExpandedPredicates.insert(MakePredicateLiteral(P)).first;
}
bool SemaAMDGPU::IsPredicate(Expr *E) const {
diff --git a/clang/test/AST/ast-print-amdgcn-predicate.c b/clang/test/AST/ast-print-amdgcn-predicate.c
new file mode 100644
index 0000000000000..1da7f78f8ac2f
--- /dev/null
+++ b/clang/test/AST/ast-print-amdgcn-predicate.c
@@ -0,0 +1,104 @@
+// REQUIRES: amdgpu-registered-target
+
+// Regression test for https://github.com/llvm/llvm-project/issues/199563:
+// SemaAMDGPU::ExpandAMDGPUPredicateBuiltIn used to synthesize an
+// IntegerLiteral of type _Bool/bool to replace
+// __builtin_amdgcn_is_invocable / __builtin_amdgcn_processor_is calls. No
+// other clang producer creates that shape, and StmtPrinter has no case for
+// it, so -ast-print on the resulting if-condition crashed via
+// llvm_unreachable. The fix synthesises a CXXBoolLiteralExpr when
+// LangOpts.Bool is set (C++, C23, OpenCL, HIP) and an int IntegerLiteral
+// otherwise (pre-C23 C). The matrix below covers every dispatch arm.
+
+// C11 (pre-C23, LangOpts.Bool=false): IntegerLiteral 'int'.
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx942 -std=c11 \
+// RUN: -ast-print %s | FileCheck --check-prefix=INT-TRUE %s
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx900 -std=c11 \
+// RUN: -ast-print %s | FileCheck --check-prefix=INT-FALSE %s
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx942 -std=c11 \
+// RUN: -ast-dump %s | FileCheck --check-prefix=INT-DUMP %s
+
+// C23 (LangOpts.Bool=true): CXXBoolLiteralExpr 'bool'.
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx942 -std=c23 \
+// RUN: -ast-print %s | FileCheck --check-prefix=BOOL-TRUE %s
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx900 -std=c23 \
+// RUN: -ast-print %s | FileCheck --check-prefix=BOOL-FALSE %s
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx942 -std=c23 \
+// RUN: -ast-dump %s | FileCheck --check-prefix=BOOL-DUMP %s
+
+// C++17 (LangOpts.Bool=true): same as C23.
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx942 -x c++ \
+// RUN: -std=c++17 -ast-print %s | FileCheck --check-prefix=BOOL-TRUE %s
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx900 -x c++ \
+// RUN: -std=c++17 -ast-print %s | FileCheck --check-prefix=BOOL-FALSE %s
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx942 -x c++ \
+// RUN: -std=c++17 -ast-dump %s | FileCheck --check-prefix=BOOL-DUMP %s
+
+// HIP device compilation (the originally-reported scenario): C++ under HIP
+// mode with -fcuda-is-device. LangOpts.Bool=true, so same as C23/C++17.
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx942 -x hip \
+// RUN: -fcuda-is-device -ast-print %s \
+// RUN: | FileCheck --check-prefix=BOOL-TRUE %s
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx900 -x hip \
+// RUN: -fcuda-is-device -ast-print %s \
+// RUN: | FileCheck --check-prefix=BOOL-FALSE %s
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx942 -x hip \
+// RUN: -fcuda-is-device -ast-dump %s \
+// RUN: | FileCheck --check-prefix=BOOL-DUMP %s
+
+#if defined(__HIP__) || defined(__CUDA__)
+#define __device__ __attribute__((device))
+#else
+#define __device__
+#endif
+
+// `__builtin_amdgcn_is_invocable` evaluates its argument unevaluated, so the
+// builtin reference itself does not need to be callable in this context.
+__device__ void use_is_invocable(void) {
+ if (__builtin_amdgcn_is_invocable(__builtin_amdgcn_flat_atomic_fadd_f32))
+ (void)0;
+}
+
+__device__ void use_processor_is(void) {
+ if (__builtin_amdgcn_processor_is("gfx942"))
+ (void)0;
+}
+
+// -ast-print: only the if-condition shape matters; anchor each check to its
+// function so the two if-stmts can't cross-match.
+
+// INT-TRUE-LABEL: use_is_invocable
+// INT-TRUE: if (1)
+// INT-TRUE-LABEL: use_processor_is
+// INT-TRUE: if (1)
+
+// INT-FALSE-LABEL: use_is_invocable
+// INT-FALSE: if (0)
+// INT-FALSE-LABEL: use_processor_is
+// INT-FALSE: if (0)
+
+// BOOL-TRUE-LABEL: use_is_invocable
+// BOOL-TRUE: if (true)
+// BOOL-TRUE-LABEL: use_processor_is
+// BOOL-TRUE: if (true)
+
+// BOOL-FALSE-LABEL: use_is_invocable
+// BOOL-FALSE: if (false)
+// BOOL-FALSE-LABEL: use_processor_is
+// BOOL-FALSE: if (false)
+
+// -ast-dump: confirm the AST node class under each function's IfStmt.
+
+// INT-DUMP-LABEL: FunctionDecl {{.*}} use_is_invocable
+// INT-DUMP: IfStmt
+// INT-DUMP-NEXT: IntegerLiteral {{.*}} 'int' 1
+// INT-DUMP-LABEL: FunctionDecl {{.*}} use_processor_is
+// INT-DUMP: IfStmt
+// INT-DUMP-NEXT: IntegerLiteral {{.*}} 'int' 1
+
+// BOOL-DUMP-LABEL: FunctionDecl {{.*}} use_is_invocable
+// BOOL-DUMP: IfStmt
+// BOOL-DUMP-NEXT: CXXBoolLiteralExpr {{.*}} 'bool' true
+// BOOL-DUMP-LABEL: FunctionDecl {{.*}} use_processor_is
+// BOOL-DUMP: IfStmt
+// BOOL-DUMP-NEXT: CXXBoolLiteralExpr {{.*}} 'bool' true
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shiltian
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Looks reasonable to me.
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Better direction, thanks.
| CXXBoolLiteralExpr(Kind == tok::kw_true, Context.BoolTy, OpLoc); | ||
| } | ||
|
|
||
| ExprResult Sema::BuildBoolLiteral(SourceLocation Loc, bool Value) { |
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Shouldn't this be in SemaExpr.cpp and not SemaExprCXX because it handles both C/C++?
ExpandAMDGPUPredicateBuiltIn synthesized an IntegerLiteral typed _Bool/bool -- a shape no other producer creates, and one that StmtPrinter::VisitIntegerLiteral has no case for. -ast-print on the resulting if-condition hit llvm_unreachable. Factor the canonical-boolean-literal logic that already lived inline in SemaObjC::ActOnObjCBoolLiteral into a shared Sema::BuildBoolLiteral helper, and use it from both ObjC and the AMDGPU predicate expansion: - C++: CXXBoolLiteralExpr 'bool' - C: IntegerLiteral 'int' implicit-cast to _Bool Fixes llvm#199563
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| @@ -760,13 +760,11 @@ Expr *SemaAMDGPU::ExpandAMDGPUPredicateBuiltIn(Expr *E) { | |||
| CallExpr *CE = cast<CallExpr>(E->IgnoreParens()); | |||
| ASTContext &Ctx = getASTContext(); | |||
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Yes.
BoolTy is used below elsewhere.
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/66/builds/31321 Here is the relevant piece of the build log for the reference |
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ExpandAMDGPUPredicateBuiltIn synthesized an IntegerLiteral typed _Bool/bool — a shape no other producer creates, and one that StmtPrinter::VisitIntegerLiteral has no case for. -ast-print on the resulting if-condition hit llvm_unreachable.
Emit the canonical boolean literal instead:
In the C case this matches what <stdbool.h>'s true/false macros expand to.
Fixes #199563