llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: OverMighty (overmighty) <details> <summary>Changes</summary> See https://github.com/llvm/llvm-project/pull/86577#discussion_r1540069558. cc @<!-- -->efriedma-quic @<!-- -->nickdesaulniers --- Full diff: https://github.com/llvm/llvm-project/pull/86742.diff 2 Files Affected: - (modified) clang/lib/AST/ExprConstant.cpp (+20-10) - (added) clang/test/Sema/constant-builtins-all-args-evaluated.cpp (+39) ``````````diff diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp index 5a36621dc5cce2..dae8f32fc02951 100644 --- a/clang/lib/AST/ExprConstant.cpp +++ b/clang/lib/AST/ExprConstant.cpp @@ -12361,12 +12361,17 @@ bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E, if (!EvaluateInteger(E->getArg(0), Val, Info)) return false; + std::optional<APSInt> Fallback; + if (BuiltinOp == Builtin::BI__builtin_clzg && E->getNumArgs() > 1) { + APSInt FallbackTemp; + if (!EvaluateInteger(E->getArg(1), FallbackTemp, Info)) + return false; + Fallback = FallbackTemp; + } + if (!Val) { - if (BuiltinOp == Builtin::BI__builtin_clzg && E->getNumArgs() > 1) { - if (!EvaluateInteger(E->getArg(1), Val, Info)) - return false; - return Success(Val, E); - } + if (Fallback) + return Success(*Fallback, E); // When the argument is 0, the result of GCC builtins is undefined, // whereas for Microsoft intrinsics, the result is the bit-width of the @@ -12425,12 +12430,17 @@ bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E, if (!EvaluateInteger(E->getArg(0), Val, Info)) return false; + std::optional<APSInt> Fallback; + if (BuiltinOp == Builtin::BI__builtin_ctzg && E->getNumArgs() > 1) { + APSInt FallbackTemp; + if (!EvaluateInteger(E->getArg(1), FallbackTemp, Info)) + return false; + Fallback = FallbackTemp; + } + if (!Val) { - if (BuiltinOp == Builtin::BI__builtin_ctzg && E->getNumArgs() > 1) { - if (!EvaluateInteger(E->getArg(1), Val, Info)) - return false; - return Success(Val, E); - } + if (Fallback) + return Success(*Fallback, E); return Error(E); } diff --git a/clang/test/Sema/constant-builtins-all-args-evaluated.cpp b/clang/test/Sema/constant-builtins-all-args-evaluated.cpp new file mode 100644 index 00000000000000..0dee74ddf690cf --- /dev/null +++ b/clang/test/Sema/constant-builtins-all-args-evaluated.cpp @@ -0,0 +1,39 @@ +// RUN: %clang_cc1 -fsyntax-only -verify %s +// expected-no-diagnostics + +constexpr int increment(int& x) { + x++; + return x; +} + +constexpr int test_clzg_0() { + int x = 0; + [[maybe_unused]] int unused = __builtin_clzg(0U, increment(x)); + return x; +} + +static_assert(test_clzg_0() == 1); + +constexpr int test_clzg_1() { + int x = 0; + [[maybe_unused]] int unused = __builtin_clzg(1U, increment(x)); + return x; +} + +static_assert(test_clzg_1() == 1); + +constexpr int test_ctzg_0() { + int x = 0; + [[maybe_unused]] int unused = __builtin_ctzg(0U, increment(x)); + return x; +} + +static_assert(test_ctzg_0() == 1); + +constexpr int test_ctzg_1() { + int x = 0; + [[maybe_unused]] int unused = __builtin_ctzg(1U, increment(x)); + return x; +} + +static_assert(test_ctzg_1() == 1); `````````` </details> https://github.com/llvm/llvm-project/pull/86742 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
