Author: Florian Hahn Date: 2020-08-21T16:50:56+01:00 New Revision: bc72a3ab949e14b990c080985fc1e74475f1e7d2
URL: https://github.com/llvm/llvm-project/commit/bc72a3ab949e14b990c080985fc1e74475f1e7d2 DIFF: https://github.com/llvm/llvm-project/commit/bc72a3ab949e14b990c080985fc1e74475f1e7d2.diff LOG: [Constants] Handle FNeg in getWithOperands. Currently ConstantExpr::getWithOperands does not handle FNeg and subsequently treats FNeg as binary operator, leading to an assertion failure or segmentation fault if built without assertions. Originally I reproduced this with llvm-dis on a bitcode file, which I unfortunately cannot share and also cannot really reduce. But PR45426 describes the same issue and has a reproducer with Clang, so I'll go with that. Reviewed By: aprantl Differential Revision: https://reviews.llvm.org/D86274 Added: clang/test/CodeGen/constantexpr-fneg.c Modified: llvm/lib/IR/Constants.cpp Removed: ################################################################################ diff --git a/clang/test/CodeGen/constantexpr-fneg.c b/clang/test/CodeGen/constantexpr-fneg.c new file mode 100644 index 000000000000..57f616437516 --- /dev/null +++ b/clang/test/CodeGen/constantexpr-fneg.c @@ -0,0 +1,20 @@ +// RUN: %clang_cc1 -emit-llvm-bc -disable-llvm-passes -o %t.bc %s +// RUN: llvm-dis %t.bc -o - | FileCheck %s + +// Test case for PR45426. Make sure we do not crash while writing bitcode +// containing a simplify-able fneg constant expression. Check that the created +// bitcode file can be disassembled and has the constant expressions simplified. +// +// CHECK-LABEL define i32 @main() +// CHECK: entry: +// CHECK-NEXT: %retval = alloca i32 +// CHECK-NEXT: store i32 0, i32* %retval +// CHECK-NEXT: [[LV:%.*]] = load float*, float** @c +// CHECK-NEXT: store float 1.000000e+00, float* [[LV]], align 4 +// CHECK-NEXT: ret i32 -1 + +int a[], b; +float *c; +int main() { + return -(*c = &b != a); +} diff --git a/llvm/lib/IR/Constants.cpp b/llvm/lib/IR/Constants.cpp index b252ef71c8ee..1cd2ced46930 100644 --- a/llvm/lib/IR/Constants.cpp +++ b/llvm/lib/IR/Constants.cpp @@ -1441,6 +1441,8 @@ Constant *ConstantExpr::getWithOperands(ArrayRef<Constant *> Ops, Type *Ty, OnlyIfReducedTy); case Instruction::ExtractValue: return ConstantExpr::getExtractValue(Ops[0], getIndices(), OnlyIfReducedTy); + case Instruction::FNeg: + return ConstantExpr::getFNeg(Ops[0]); case Instruction::ShuffleVector: return ConstantExpr::getShuffleVector(Ops[0], Ops[1], getShuffleMask(), OnlyIfReducedTy); _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
