clang/test/CodeGen/bpf-preserve-static-offset-lvalue.c

   1 // NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 2
   2 // REQUIRES: bpf-registered-target
   3 // RUN: %clang_cc1 -triple bpf -disable-llvm-passes -emit-llvm -o - %s | FileCheck %s
   4
   5 // Check that call to preserve.static.offset is generated when field of
   6 // a struct marked with __attribute__((preserve_static_offset)) is accessed.
   7
   8 #define __ctx __attribute__((preserve_static_offset))
   9
  10 struct foo {
  11   int a;
  12 } __ctx;
  13
  14 // CHECK-LABEL: define dso_local void @lvalue
  15 // CHECK-SAME: (ptr noundef [[P:%.*]]) #[[ATTR0:[0-9]+]] {
  16 // CHECK-NEXT:  entry:
  17 // CHECK-NEXT:    [[P_ADDR:%.*]] = alloca ptr, align 8
  18 // CHECK-NEXT:    store ptr [[P]], ptr [[P_ADDR]], align 8
  19 // CHECK-NEXT:    [[TMP0:%.*]] = load ptr, ptr [[P_ADDR]], align 8
  20 // CHECK-NEXT:    [[TMP1:%.*]] = call ptr @llvm.preserve.static.offset(ptr [[TMP0]])
  21 // CHECK-NEXT:    [[A:%.*]] = getelementptr inbounds nuw [[STRUCT_FOO:%.*]], ptr [[TMP1]], i32 0, i32 0
  22 // CHECK-NEXT:    store i32 42, ptr [[A]], align 4
  23 // CHECK-NEXT:    ret void
  24 //
  25 void lvalue(struct foo *p) {
  26   p->a = 42;
  27 }