| 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 | |
| 4 | // In all tests, make sure that no expect is generated if optimizations are off. |
| 5 | // If optimizations are on, generate the correct expect and preserve other necessary operations. |
| 6 | |
| 7 | int expect_taken(int x) { |
| 8 | // ALL-LABEL: define i32 @expect_taken |
| 9 | // O1: call i64 @llvm.expect.i64(i64 {{%.*}}, i64 1) |
| 10 | // O0-NOT: @llvm.expect |
| 11 | |
| 12 | if (__builtin_expect (x, 1)) |
| 13 | return 0; |
| 14 | return x; |
| 15 | } |
| 16 | |
| 17 | |
| 18 | int expect_not_taken(int x) { |
| 19 | // ALL-LABEL: define i32 @expect_not_taken |
| 20 | // O1: call i64 @llvm.expect.i64(i64 {{%.*}}, i64 0) |
| 21 | // O0-NOT: @llvm.expect |
| 22 | |
| 23 | if (__builtin_expect (x, 0)) |
| 24 | return 0; |
| 25 | return x; |
| 26 | } |
| 27 | |
| 28 | |
| 29 | int x; |
| 30 | int y(void); |
| 31 | void foo(); |
| 32 | |
| 33 | void expect_value_side_effects() { |
| 34 | // ALL-LABEL: define void @expect_value_side_effects() |
| 35 | // ALL: [[CALL:%.*]] = call i32 @y |
| 36 | // O1: [[SEXT:%.*]] = sext i32 [[CALL]] to i64 |
| 37 | // O1: call i64 @llvm.expect.i64(i64 {{%.*}}, i64 [[SEXT]]) |
| 38 | // O0-NOT: @llvm.expect |
| 39 | |
| 40 | if (__builtin_expect (x, y())) |
| 41 | foo (); |
| 42 | } |
| 43 | |
| 44 | |
| 45 | // Make sure that issigprocmask() is called before bar()? |
| 46 | // There's no compare, so there's nothing to expect? |
| 47 | // rdar://9330105 |
| 48 | void isigprocmask(void); |
| 49 | long bar(); |
| 50 | |
| 51 | int main() { |
| 52 | // ALL-LABEL: define i32 @main() |
| 53 | // ALL: call void @isigprocmask() |
| 54 | // ALL: [[CALL:%.*]] = call i64 (...) @bar() |
| 55 | // O1: call i64 @llvm.expect.i64(i64 0, i64 [[CALL]]) |
| 56 | // O0-NOT: @llvm.expect |
| 57 | |
| 58 | (void) __builtin_expect((isigprocmask(), 0), bar()); |
| 59 | } |
| 60 | |
| 61 | |
| 62 | int switch_cond(int x) { |
| 63 | // ALL-LABEL: define i32 @switch_cond |
| 64 | // O1: call i64 @llvm.expect.i64(i64 {{%.*}}, i64 5) |
| 65 | // O0-NOT: @llvm.expect |
| 66 | |
| 67 | switch(__builtin_expect(x, 5)) { |
| 68 | default: |
| 69 | return 0; |
| 70 | case 0: |
| 71 | case 1: |
| 72 | case 2: |
| 73 | return 1; |
| 74 | case 5: |
| 75 | return 5; |
| 76 | }; |
| 77 | |
| 78 | return 0; |
| 79 | } |
| 80 | |
| 81 | int variable_expected(int stuff) { |
| 82 | // ALL-LABEL: define i32 @variable_expected( |
| 83 | // O1: call i64 @llvm.expect.i64(i64 {{%.*}}, i64 {{%.*}}) |
| 84 | // O0-NOT: @llvm.expect |
| 85 | |
| 86 | int res = 0; |
| 87 | |
| 88 | switch (__builtin_expect(stuff, stuff)) { |
| 89 | case 0: |
| 90 | res = 1; |
| 91 | break; |
| 92 | default: |
| 93 | break; |
| 94 | } |
| 95 | |
| 96 | return res; |
| 97 | } |
| 98 | |