1 // RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s -O1 -disable-llvm-passes | FileCheck %s --check-prefix=ALL --check-prefix=O1
2 // RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s -O0 | FileCheck %s --check-prefix=ALL --check-prefix=O0
3 extern int global;
4
expect_taken(int x)5 int expect_taken(int x) {
6 // ALL-LABEL: expect_taken
7 // O1: call i64 @llvm.expect.with.probability.i64(i64 {{%.*}}, i64 1, double 9.000000e-01)
8 // O0-NOT: @llvm.expect.with.probability
9
10 if (__builtin_expect_with_probability(x == 100, 1, 0.9)) {
11 return 0;
12 }
13 return x;
14 }
15
expect_not_taken(int x)16 int expect_not_taken(int x) {
17 // ALL-LABEL: expect_not_taken
18 // O1: call i64 @llvm.expect.with.probability.i64(i64 {{%.*}}, i64 0, double 9.000000e-01)
19 // O0-NOT: @llvm.expect.with.probability
20
21 if (__builtin_expect_with_probability(x == 100, 0, 0.9)) {
22 return 0;
23 }
24 return x;
25 }
26
27 struct S {
28 static constexpr int prob = 1;
29 };
30
31 template<typename T>
expect_taken_template(int x)32 int expect_taken_template(int x) {
33 // ALL-LABEL: expect_taken_template
34 // O1: call i64 @llvm.expect.with.probability.i64(i64 {{%.*}}, i64 1, double 1.000000e+00)
35 // O0-NOT: @llvm.expect.with.probability
36
37 if (__builtin_expect_with_probability (x == 100, 1, T::prob)) {
38 return 0;
39 }
40 return x;
41 }
42
f()43 int f() {
44 return expect_taken_template<S>(global);
45 }
46
47 int x;
48 extern "C" {
49 int y(void);
50 }
51 void foo();
52
expect_value_side_effects()53 void expect_value_side_effects() {
54 // ALL-LABEL: expect_value_side_effects
55 // ALL: [[CALL:%.*]] = call i32 @y
56 // O1: [[SEXT:%.*]] = sext i32 [[CALL]] to i64
57 // O1: call i64 @llvm.expect.with.probability.i64(i64 {{%.*}}, i64 [[SEXT]], double 6.000000e-01)
58 // O0-NOT: @llvm.expect.with.probability
59
60 if (__builtin_expect_with_probability(x, y(), 0.6))
61 foo();
62 }
63
switch_cond(int x)64 int switch_cond(int x) {
65 // ALL-LABEL: switch_cond
66 // O1: call i64 @llvm.expect.with.probability.i64(i64 {{%.*}}, i64 1, double 8.000000e-01)
67 // O0-NOT: @llvm.expect.with.probability
68
69 switch (__builtin_expect_with_probability(x, 1, 0.8)) {
70 case 0:
71 x = x + 0;
72 case 1:
73 x = x + 1;
74 case 2:
75 x = x + 2;
76 case 5:
77 x = x + 5;
78 default:
79 x = x + 6;
80 }
81 return x;
82 }
83
84 constexpr double prob = 0.8;
85
variable_expected(int stuff)86 int variable_expected(int stuff) {
87 // ALL-LABEL: variable_expected
88 // O1: call i64 @llvm.expect.with.probability.i64(i64 {{%.*}}, i64 {{%.*}}, double 8.000000e-01)
89 // O0-NOT: @llvm.expect.with.probability
90
91 int res = 0;
92
93 switch(__builtin_expect_with_probability(stuff, stuff, prob)) {
94 case 0:
95 res = 1;
96 break;
97 default:
98 break;
99 }
100 return res;
101 }
102