Author: erichkeane Date: Thu Jul 5 08:52:58 2018 New Revision: 336364 URL: http://llvm.org/viewvc/llvm-project?rev=336364&view=rev Log: Fix __builtin_*_overflow when out-param isn't constexpr
As brought up on cfe-commits[1], r334650 causes the dependency of the out parameter to the __builtin_*_overflow functions to be ignored. The result was a usage that was otherwise constexpr (both operands to the operation were constexpr) would be evaluated, but the out parameter wouldn't be modified, so it would still be 'undef'. This patch correctly handles the return value of handleAssignment to ensure that this value is properly considered/evaluated. [1] http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180702/233667.html Modified: cfe/trunk/lib/AST/ExprConstant.cpp cfe/trunk/test/CodeGenCXX/builtins.cpp Modified: cfe/trunk/lib/AST/ExprConstant.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ExprConstant.cpp?rev=336364&r1=336363&r2=336364&view=diff ============================================================================== --- cfe/trunk/lib/AST/ExprConstant.cpp (original) +++ cfe/trunk/lib/AST/ExprConstant.cpp Thu Jul 5 08:52:58 2018 @@ -8346,7 +8346,8 @@ bool IntExprEvaluator::VisitBuiltinCallE } APValue APV{Result}; - handleAssignment(Info, E, ResultLValue, ResultType, APV); + if (!handleAssignment(Info, E, ResultLValue, ResultType, APV)) + return false; return Success(DidOverflow, E); } } Modified: cfe/trunk/test/CodeGenCXX/builtins.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/builtins.cpp?rev=336364&r1=336363&r2=336364&view=diff ============================================================================== --- cfe/trunk/test/CodeGenCXX/builtins.cpp (original) +++ cfe/trunk/test/CodeGenCXX/builtins.cpp Thu Jul 5 08:52:58 2018 @@ -30,3 +30,19 @@ long y = __builtin_abs(-2l); extern const char char_memchr_arg[32]; char *memchr_result = __builtin_char_memchr(char_memchr_arg, 123, 32); // CHECK: call i8* @memchr(i8* getelementptr inbounds ([32 x i8], [32 x i8]* @char_memchr_arg, i32 0, i32 0), i32 123, i64 32) + +int constexpr_overflow_result() { + constexpr int x = 1; + // CHECK: alloca i32 + constexpr int y = 2; + // CHECK: alloca i32 + int z; + // CHECK: [[Z:%.+]] = alloca i32 + + __builtin_sadd_overflow(x, y, &z); + return z; + // CHECK: [[RET_PTR:%.+]] = extractvalue { i32, i1 } %0, 0 + // CHECK: store i32 [[RET_PTR]], i32* [[Z]] + // CHECK: [[RET_VAL:%.+]] = load i32, i32* [[Z]] + // CHECK: ret i32 [[RET_VAL]] +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
