clang/test/CodeGen/attr-naked.c

   1 // RUN: %clang_cc1 -triple x86_64-apple-macosx10.7.0 %s -emit-llvm -o - | FileCheck %s
   2
   3 void t1(void) __attribute__((naked));
   4
   5 // Basic functionality check
   6 // (Note that naked needs to imply noinline to work properly.)
   7 // CHECK: define{{.*}} void @t1() [[NAKED_OPTNONE:#[0-9]+]] {
   8 void t1(void)
   9 {
  10 }
  11
  12 // Make sure this doesn't explode in the verifier.
  13 // (It doesn't really make sense, but it isn't invalid.)
  14 // CHECK: define{{.*}} void @t2() [[NAKED:#[0-9]+]] {
  15 __attribute((naked, always_inline)) void t2(void) {
  16 }
  17
  18 // Make sure not to generate prolog or epilog for naked functions.
  19 __attribute((naked)) void t3(int x) {
  20 // CHECK: define{{.*}} void @t3(i32 noundef %0)
  21 // CHECK-NOT: alloca
  22 // CHECK-NOT: store
  23 // CHECK: unreachable
  24 }
  25
  26 // Make sure naked functions do not attempt to evaluate parameters with a
  27 // variably-modified type. Naked functions get no prolog, so this evaluation
  28 // should not take place.
  29 __attribute__((naked)) void t4(int len, char x[len]) {
  30   // CHECK: define{{.*}} void @t4(i32 noundef{{.*}}, ptr noundef{{.*}})
  31   // CHECK: unreachable
  32 }
  33
  34 // CHECK: attributes [[NAKED_OPTNONE]] = { naked noinline nounwind optnone{{.*}} }
  35 // CHECK: attributes [[NAKED]] = { naked noinline nounwind{{.*}} }