clang/test/CodeGen/aggregate-assign-call.c

   1 // RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -O1 -emit-llvm -o - %s | FileCheck %s --check-prefixes=O1
   2 // RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -O0 -emit-llvm -o - %s | FileCheck %s --check-prefix=O0
   3 //
   4 // Ensure that we place appropriate lifetime markers around indirectly returned
   5 // temporaries, and that the lifetime.ends appear in a timely manner.
   6 //
   7 // -O1 is used so lifetime markers actually get emitted and optnone is added
   8 // to avoid elimination of lifetime markers by optimizations.
   9
  10 struct S {
  11   int ns[40];
  12 };
  13
  14 struct S foo(void);
  15
  16 // CHECK-LABEL: define dso_local void @bar
  17 __attribute__((optnone))
  18 struct S bar(void) {
  19   // O0-NOT: @llvm.lifetime.start
  20   // O0-NOT: @llvm.lifetime.end
  21
  22   struct S r;
  23   // O1: %[[TMP1_ALLOCA:[^ ]+]] = alloca %struct.S
  24   // O1: %[[TMP2_ALLOCA:[^ ]+]] = alloca %struct.S
  25   // O1: %[[TMP3_ALLOCA:[^ ]+]] = alloca %struct.S
  26
  27   // O1: call void @llvm.lifetime.start.p0({{[^,]*}}, ptr %[[TMP1_ALLOCA]])
  28   // O1: call void @foo
  29   r = foo();
  30   // O1: memcpy
  31   // O1: call void @llvm.lifetime.end.p0({{[^,]*}}, ptr %[[TMP1_ALLOCA]])
  32
  33   // O1: call void @llvm.lifetime.start.p0({{[^,]*}}, ptr %[[TMP2_ALLOCA]])
  34   // O1: call void @foo
  35   r = foo();
  36   // O1: memcpy
  37   // O1: call void @llvm.lifetime.end.p0({{[^,]*}}, ptr %[[TMP2_ALLOCA]])
  38
  39   // O1: call void @llvm.lifetime.start.p0({{[^,]*}}, ptr %[[TMP3_ALLOCA]])
  40   // O1: call void @foo
  41   r = foo();
  42   // O1: memcpy
  43   // O1: call void @llvm.lifetime.end.p0({{[^,]*}}, ptr %[[TMP3_ALLOCA]])
  44
  45   return r;
  46 }
  47
  48 struct S foo_int(int);
  49
  50 // Be sure that we're placing the lifetime.end so that all paths go through it.
  51 // CHECK-LABEL: define dso_local void @baz
  52 __attribute__((optnone))
  53 struct S baz(int i, volatile int *j) {
  54   // O0-NOT: @llvm.lifetime.start
  55   // O0-NOT: @llvm.lifetime.end
  56
  57   struct S r;
  58   // O1: %[[TMP1_ALLOCA:[^ ]+]] = alloca %struct.S
  59   // O1: %[[TMP2_ALLOCA:[^ ]+]] = alloca %struct.S
  60
  61   do {
  62     // O1: call void @llvm.lifetime.start.p0({{[^,]*}}, ptr %[[TMP1_ALLOCA]])
  63     //
  64     // O1: call void @llvm.lifetime.end.p0({{[^,]*}}, ptr %[[TMP1_ALLOCA]])
  65     //
  66     // O1: call void @foo_int(ptr dead_on_unwind writable sret(%struct.S) align 4 %[[TMP1_ALLOCA]],
  67     // O1: call void @llvm.memcpy
  68     // O1: call void @llvm.lifetime.end.p0({{[^,]*}}, ptr %[[TMP1_ALLOCA]])
  69     // O1: call void @llvm.lifetime.start.p0({{[^,]*}}, ptr %[[TMP2_ALLOCA]])
  70     // O1: call void @foo_int(ptr dead_on_unwind writable sret(%struct.S) align 4 %[[TMP2_ALLOCA]],
  71     // O1: call void @llvm.memcpy
  72     // O1: call void @llvm.lifetime.end.p0({{[^,]*}}, ptr %[[TMP2_ALLOCA]])
  73     r = foo_int(({
  74       if (*j)
  75         break;
  76       i++;
  77     }));
  78
  79     r = foo_int(i++);
  80    } while (1);
  81
  82   return r;
  83 }