mirror of
https://github.com/capstone-engine/llvm-capstone.git
synced 2025-05-13 17:37:00 +00:00
1228becf7d
This patch deduces `noundef` attributes for return values. IIUC, a function returns `noundef` values iff all of its return values are guaranteed not to be `undef` or `poison`. Definition of `noundef` from LangRef: ``` noundef This attribute applies to parameters and return values. If the value representation contains any undefined or poison bits, the behavior is undefined. Note that this does not refer to padding introduced by the type’s storage representation. ``` Alive2: https://alive2.llvm.org/ce/z/g8Eis6 Compile-time impact: http://llvm-compile-time-tracker.com/compare.php?from=30dcc33c4ea3ab50397a7adbe85fe977d4a400bd&to=c5e8738d4bfbf1e97e3f455fded90b791f223d74&stat=instructions:u |stage1-O3|stage1-ReleaseThinLTO|stage1-ReleaseLTO-g|stage1-O0-g|stage2-O3|stage2-O0-g|stage2-clang| |--|--|--|--|--|--|--| |+0.01%|+0.01%|-0.01%|+0.01%|+0.03%|-0.04%|+0.01%| The motivation of this patch is to reduce the number of `freeze` insts and enable more optimizations.
65 lines
2.6 KiB
C
65 lines
2.6 KiB
C
// RUN: %clang_cc1 -triple i386-unknown-linux-gnu -emit-llvm -o - %s | FileCheck %s
|
|
// RUN: %clang_cc1 -triple i386-unknown-linux-gnu -O2 -emit-llvm -o - %s | FileCheck %s
|
|
// RUN: %clang_cc1 -triple i386-unknown-linux-gnu -fsanitize=thread -O2 -emit-llvm -o - %s | FileCheck %s --check-prefix=SAN
|
|
// RUN: %clang_cc1 -triple i386-unknown-linux-gnu -fsanitize=address -O2 -emit-llvm -o - %s | FileCheck %s --check-prefix=SAN
|
|
// RUN: %clang_cc1 -triple i386-unknown-linux-gnu -fsanitize=memory -O2 -emit-llvm -o - %s | FileCheck %s --check-prefix=SAN
|
|
// RUN: %clang_cc1 -triple arm64-apple-macosx -emit-llvm -o - %s | FileCheck %s
|
|
// RUN: %clang_cc1 -triple x86_64-apple-macosx -emit-llvm -o - %s | FileCheck %s
|
|
// RUN: %clang_cc1 -triple arm64-apple-macosx -O2 -emit-llvm -o - %s | FileCheck %s
|
|
// RUN: %clang_cc1 -triple x86_64-apple-macosx -O2 -emit-llvm -o - %s | FileCheck %s
|
|
// RUN: %clang_cc1 -triple arm64-apple-macosx -fsanitize=thread -O2 -emit-llvm -o - %s | FileCheck %s --check-prefix=MACSAN
|
|
// RUN: %clang_cc1 -triple x86_64-apple-macosx -fsanitize=thread -O2 -emit-llvm -o - %s | FileCheck %s --check-prefix=MACSAN
|
|
// RUN: %clang_cc1 -triple arm64-apple-macosx -fsanitize=address -O2 -emit-llvm -o - %s | FileCheck %s --check-prefix=MACSAN
|
|
// RUN: %clang_cc1 -triple x86_64-apple-macosx -fsanitize=address -O2 -emit-llvm -o - %s | FileCheck %s --check-prefix=MACSAN
|
|
|
|
int foo(int) __attribute__ ((ifunc("foo_ifunc")));
|
|
|
|
static int f1(int i) {
|
|
return i + 1;
|
|
}
|
|
|
|
static int f2(int i) {
|
|
return i + 2;
|
|
}
|
|
|
|
typedef int (*foo_t)(int);
|
|
|
|
int global;
|
|
|
|
static foo_t foo_ifunc(void) {
|
|
return global ? f1 : f2;
|
|
}
|
|
|
|
int bar(void) {
|
|
return foo(1);
|
|
}
|
|
|
|
extern void goo(void);
|
|
|
|
void bar2(void) {
|
|
goo();
|
|
}
|
|
|
|
extern void goo(void) __attribute__ ((ifunc("goo_ifunc")));
|
|
|
|
void* goo_ifunc(void) {
|
|
return 0;
|
|
}
|
|
// CHECK: @foo = ifunc i32 (i32), ptr @foo_ifunc
|
|
// CHECK: @goo = ifunc void (), ptr @goo_ifunc
|
|
|
|
// CHECK: call i32 @foo(i32
|
|
// CHECK: call void @goo()
|
|
|
|
// SAN: define internal nonnull {{(noundef )?}}ptr @foo_ifunc() #[[#FOO_IFUNC:]] {
|
|
// MACSAN: define internal nonnull {{(noundef )?}}ptr @foo_ifunc() #[[#FOO_IFUNC:]] {
|
|
|
|
// SAN: define dso_local noalias {{(noundef )?}}ptr @goo_ifunc() #[[#GOO_IFUNC:]] {
|
|
// MACSAN: define noalias {{(noundef )?}}ptr @goo_ifunc() #[[#GOO_IFUNC:]] {
|
|
|
|
// SAN-DAG: attributes #[[#FOO_IFUNC]] = {{{.*}} disable_sanitizer_instrumentation {{.*}}
|
|
// MACSAN-DAG: attributes #[[#FOO_IFUNC]] = {{{.*}} disable_sanitizer_instrumentation {{.*}}
|
|
|
|
// SAN-DAG: attributes #[[#GOO_IFUNC]] = {{{.*}} disable_sanitizer_instrumentation {{.*}}
|
|
// MACSAN-DAG: attributes #[[#GOO_IFUNC]] = {{{.*}} disable_sanitizer_instrumentation {{.*}}
|