llvm-project/clang/test/CodeGen/constantexpr-fneg.c
Nikita Popov 63dc31b68b Reapply [IR] Avoid creating icmp/fcmp constant expressions (#92885)
Reapply after https://github.com/llvm/llvm-project/pull/93548,
which should address the lldb failure on macos.

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Do not create icmp/fcmp constant expressions in IRBuilder etc anymore,
i.e. treat them as "undesirable". This is in preparation for removing
them entirely.

Part of:
https://discourse.llvm.org/t/rfc-remove-most-constant-expressions/63179
2024-05-31 08:55:59 +02:00

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C

// 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-LABEL define i32 @main()
// CHECK: entry:
// CHECK-NEXT: %retval = alloca i32
// CHECK-NEXT: store i32 0, ptr %retval
// CHECK-NEXT: [[CMP:%.*]] = icmp ne ptr @b, @a
// CHECK-NEXT: [[ZEXT:%.*]] = zext i1 [[CMP]] to i32
// CHECK-NEXT: [[SITOFP:%.*]] = sitofp i32 [[ZEXT]] to float
// CHECK-NEXT: [[LV:%.*]] = load ptr, ptr @c
// CHECK-NEXT: store float [[SITOFP]], ptr [[LV]], align 4
// CHECK-NEXT: [[FNEG:%.*]] = fneg float [[SITOFP]]
// CHECK-NEXT: [[CONV:%.*]] = fptosi float [[FNEG]] to i32
// CHECK-NEXT: ret i32 [[CONV]]
int a[], b;
float *c;
int main(void) {
return -(*c = &b != a);
}