clang/test/CodeGen/alloc-fns-alignment.c

// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-llvm < %s | FileCheck %s

// Note: this test originally asserted that malloc/calloc/realloc got alignment
// attributes on their return pointer. However, that was reverted in
// https://reviews.llvm.org/D118804 and it now asserts that they do _NOT_ get
// align attributes.

typedef __SIZE_TYPE__ size_t;

void *malloc(size_t);
void *calloc(size_t, size_t);
void *realloc(void *, size_t);
void *aligned_alloc(size_t, size_t);

void *malloc_test(size_t n) {
  return malloc(n);
}

void *calloc_test(size_t n) {
  return calloc(1, n);
}

void *realloc_test(void *p, size_t n) {
  return realloc(p, n);
}

void *aligned_alloc_variable_test(size_t n, size_t a) {
  return aligned_alloc(a, n);
}

void *aligned_alloc_constant_test(size_t n) {
  return aligned_alloc(8, n);
}

void *aligned_alloc_large_constant_test(size_t n) {
  return aligned_alloc(4096, n);
}

// CHECK-LABEL: @malloc_test
// CHECK: call i8* @malloc

// CHECK: declare i8* @malloc

// CHECK-LABEL: @calloc_test
// CHECK: call i8* @calloc

// CHECK: declare i8* @calloc

// CHECK-LABEL: @realloc_test
// CHECK: call i8* @realloc

// CHECK: declare i8* @realloc

// CHECK-LABEL: @aligned_alloc_variable_test
// CHECK:      %[[ALLOCATED:.*]] = call i8* @aligned_alloc({{i32|i64}} noundef %[[ALIGN:.*]], {{i32|i64}} noundef %[[NBYTES:.*]])
// CHECK-NEXT: call void @llvm.assume(i1 true) [ "align"(i8* %[[ALLOCATED]], {{i32|i64}} %[[ALIGN]]) ]

// CHECK: declare i8* @aligned_alloc

// CHECK-LABEL: @aligned_alloc_constant_test
// CHECK: call align 8 i8* @aligned_alloc

// CHECK-LABEL: @aligned_alloc_large_constant_test
// CHECK: call align 4096 i8* @aligned_alloc