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// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s -O1 -disable-llvm-passes | FileCheck %s --check-prefix=ALL --check-prefix=O1
// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s -O0 | FileCheck %s --check-prefix=ALL --check-prefix=O0
// In all tests, make sure that no expect is generated if optimizations are off.
// If optimizations are on, generate the correct expect and preserve other necessary operations.
int expect_taken(int x) {
// ALL-LABEL: define i32 @expect_taken
// O1: call i64 @llvm.expect.i64(i64 {{%.*}}, i64 1)
// O0-NOT: @llvm.expect
if (__builtin_expect (x, 1))
return 0;
return x;
}
int expect_not_taken(int x) {
// ALL-LABEL: define i32 @expect_not_taken
// O1: call i64 @llvm.expect.i64(i64 {{%.*}}, i64 0)
// O0-NOT: @llvm.expect
if (__builtin_expect (x, 0))
return 0;
return x;
}
int x;
int y(void);
void foo();
void expect_value_side_effects() {
// ALL-LABEL: define void @expect_value_side_effects()
// ALL: [[CALL:%.*]] = call i32 @y
// O1: [[SEXT:%.*]] = sext i32 [[CALL]] to i64
// O1: call i64 @llvm.expect.i64(i64 {{%.*}}, i64 [[SEXT]])
// O0-NOT: @llvm.expect
if (__builtin_expect (x, y()))
foo ();
}
// Make sure that issigprocmask() is called before bar()?
// There's no compare, so there's nothing to expect?
// rdar://9330105
void isigprocmask(void);
long bar();
int main() {
// ALL-LABEL: define i32 @main()
// ALL: call void @isigprocmask()
// ALL: [[CALL:%.*]] = call i64 (...) @bar()
// O1: call i64 @llvm.expect.i64(i64 0, i64 [[CALL]])
// O0-NOT: @llvm.expect
(void) __builtin_expect((isigprocmask(), 0), bar());
}
int switch_cond(int x) {
// ALL-LABEL: define i32 @switch_cond
// O1: call i64 @llvm.expect.i64(i64 {{%.*}}, i64 5)
// O0-NOT: @llvm.expect
switch(__builtin_expect(x, 5)) {
default:
return 0;
case 0:
case 1:
case 2:
return 1;
case 5:
return 5;
};
return 0;
}
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