| // RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -fextend-variable-liveness -o - %s | FileCheck %s |
| |
| /// Tests that when we have fake uses in a function ending in a musttail call, |
| /// we emit the fake uses and their corresponding loads immediately prior to the |
| /// tail call. |
| |
| extern "C" char *bar(int *); |
| |
| // CHECK-LABEL: define dso_local ptr @foo( |
| // CHECK-SAME: ptr noundef [[E:%.*]]) |
| // CHECK-NEXT: [[ENTRY:.*:]] |
| // CHECK-NEXT: [[E_ADDR:%.*]] = alloca ptr, align 8 |
| // CHECK-NEXT: store ptr [[E]], ptr [[E_ADDR]], align 8 |
| // CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[E_ADDR]], align 8 |
| // CHECK-NEXT: [[FAKE_USE:%.*]] = load ptr, ptr [[E_ADDR]] |
| // CHECK-NEXT: notail call void (...) @llvm.fake.use(ptr [[FAKE_USE]]) |
| // CHECK-NEXT: [[CALL:%.*]] = musttail call ptr @bar(ptr noundef [[TMP0]]) |
| // CHECK-NEXT: ret ptr [[CALL]] |
| |
| // CHECK: [[BB1:.*:]] |
| // CHECK-NEXT: [[FAKE_USE1:%.*]] = load ptr, ptr [[E_ADDR]] |
| // CHECK-NEXT: notail call void (...) @llvm.fake.use(ptr [[FAKE_USE1]]) |
| // CHECK-NEXT: ret ptr undef |
| // |
| extern "C" const char *foo(int *e) { |
| [[clang::musttail]] return bar(e); |
| } |