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llvm-project/clang/test/Profile/c-ternary.c

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Retry: [profiling] Fix profile counter increment when emitting selects (PR32019) 2nd attempt: the first was in r296231, but it had a use after lifetime bug. Clang has logic to lower certain conditional expressions directly into llvm select instructions. However, it does not emit the correct profile counter increment as it does this: it emits an unconditional increment of the counter for the 'then branch', even if the value selected is from the 'else branch' (this is PR32019). That means, given the following snippet, we would report that "0" is selected twice, and that "1" is never selected: int f1(int x) { return x ? 0 : 1; ^2 ^0 } f1(0); f1(1); Fix the problem by using the instrprof_increment_step intrinsic to do the proper increment. llvm-svn: 296245
2017-02-25 14:35:45 +08:00
// RUN: %clang_cc1 -triple x86_64-apple-macosx10.11.0 -x c %s -o - -emit-llvm -fprofile-instrument=clang | FileCheck %s
// PR32019: Clang can lower some ternary operator expressions to select
// instructions. Make sure we only increment the profile counter for the
// condition when the condition evaluates to true.
// CHECK-LABEL: define i32 @f1
int f1(int x) {
Weaken test/Profile/c-ternary.c There is a bot which doesn't use '%1' as the IR name of the first argument to a function: http://lab.llvm.org:8011/builders/clang-with-thin-lto-ubuntu/builds/2050/steps/test-stage1-compiler/logs/stdio llvm-svn: 296248
2017-02-25 15:21:23 +08:00
// CHECK: [[TOBOOL:%.*]] = icmp ne i32 %{{.*}}, 0
Retry: [profiling] Fix profile counter increment when emitting selects (PR32019) 2nd attempt: the first was in r296231, but it had a use after lifetime bug. Clang has logic to lower certain conditional expressions directly into llvm select instructions. However, it does not emit the correct profile counter increment as it does this: it emits an unconditional increment of the counter for the 'then branch', even if the value selected is from the 'else branch' (this is PR32019). That means, given the following snippet, we would report that "0" is selected twice, and that "1" is never selected: int f1(int x) { return x ? 0 : 1; ^2 ^0 } f1(0); f1(1); Fix the problem by using the instrprof_increment_step intrinsic to do the proper increment. llvm-svn: 296245
2017-02-25 14:35:45 +08:00
// CHECK-NEXT: [[STEP:%.*]] = zext i1 [[TOBOOL]] to i64
// CHECK-NEXT: [[COUNTER:%.*]] = load i64, i64* getelementptr inbounds ([2 x i64], [2 x i64]* @__profc_f1, i64 0, i64 1)
// CHECK-NEXT: add i64 [[COUNTER]], [[STEP]]
// CHECK: [[COND:%.*]] = select i1 [[TOBOOL]], i32 0, i32 1
return x ? 0 : 1;
// CHECK: ret i32 [[COND]]
}