[clang] Add CodeGen tests for CWG 5xx issues #84303
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This patch covers [CWG519](https://cplusplus.github.io/CWG/issues/519.html) "Null pointer preservation in `void*` conversions ", [CWG571](https://cplusplus.github.io/CWG/issues/571.html) "References declared const".
|
@llvm/pr-subscribers-clang Author: Vlad Serebrennikov (Endilll) ChangesThis patch covers Full diff: https://github.com/llvm/llvm-project/pull/84303.diff 4 Files Affected:
diff --git a/clang/test/CXX/drs/dr519.cpp b/clang/test/CXX/drs/dr519.cpp
new file mode 100644
index 00000000000000..67c01d95ef7c6f
--- /dev/null
+++ b/clang/test/CXX/drs/dr519.cpp
@@ -0,0 +1,36 @@
+// RUN: %clang_cc1 -std=c++98 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++11 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++14 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++17 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++20 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++23 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++2c %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+
+namespace dr519 { // dr519: 2.7
+void f() {
+ int *a = 0;
+ void *v = a;
+ bool c1 = v == static_cast<void *>(0);
+
+ void *w = 0;
+ int *b = static_cast<int*>(w);
+ bool c2 = b == static_cast<int *>(0);
+}
+} // namespace dr519
+
+// We're checking that `null`s that were initially stored in `a` and `w`
+// are simply copied over all the way to respective comparisons with `null`.
+
+// CHECK-LABEL: define {{.*}} void @dr519::f()()
+// CHECK: store ptr null, ptr [[A:%.+]],
+// CHECK-NEXT: [[TEMP_A:%.+]] = load ptr, ptr [[A]]
+// CHECK-NEXT: store ptr [[TEMP_A]], ptr [[V:%.+]],
+// CHECK-NEXT: [[TEMP_V:%.+]] = load ptr, ptr [[V]]
+// CHECK-NEXT: {{.+}} = icmp eq ptr [[TEMP_V]], null
+
+// CHECK: store ptr null, ptr [[W:%.+]],
+// CHECK-NEXT: [[TEMP_W:%.+]] = load ptr, ptr [[W]]
+// CHECK-NEXT: store ptr [[TEMP_W]], ptr [[B:%.+]],
+// CHECK-NEXT: [[TEMP_B:%.+]] = load ptr, ptr [[B]]
+// CHECK-NEXT: {{.+}} = icmp eq ptr [[TEMP_B]], null
+// CHECK-LABEL: }
diff --git a/clang/test/CXX/drs/dr571.cpp b/clang/test/CXX/drs/dr571.cpp
new file mode 100644
index 00000000000000..19a85b7ddc3508
--- /dev/null
+++ b/clang/test/CXX/drs/dr571.cpp
@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 -std=c++98 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++11 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++14 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++17 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++20 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++23 %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+// RUN: %clang_cc1 -std=c++2c %s -triple x86_64-linux-gnu -emit-llvm -o - -fexceptions -fcxx-exceptions -pedantic-errors | llvm-cxxfilt -n | FileCheck %s --check-prefixes CHECK
+
+namespace dr571 { // dr571: 2.7
+ typedef int &ir;
+ int n;
+ const ir r = n;
+ // expected-warning@-1 {{'const' qualifier on reference type 'ir' (aka 'int &') has no effect}}
+ ir r2 = n;
+}
+
+// Entities have external linkage by default.
+
+// CHECK: @dr571::r = constant ptr @dr571::n
+// CHECK: @dr571::r2 = constant ptr @dr571::n
diff --git a/clang/test/CXX/drs/dr5xx.cpp b/clang/test/CXX/drs/dr5xx.cpp
index 0e1de342f6706f..426b368b390ae6 100644
--- a/clang/test/CXX/drs/dr5xx.cpp
+++ b/clang/test/CXX/drs/dr5xx.cpp
@@ -141,15 +141,7 @@ namespace dr518 { // dr518: yes c++11
// cxx98-error@-1 {{commas at the end of enumerator lists are a C++11 extension}}
}
-namespace dr519 { // dr519: yes
-// FIXME: Add a codegen test.
-#if __cplusplus >= 201103L
-#define fold(x) (__builtin_constant_p(x) ? (x) : (x))
- int test[fold((int*)(void*)0) ? -1 : 1];
-#undef fold
-#endif
-}
-
+// dr519 is in dr519.cpp
// dr520: na
// dr521: no
@@ -800,14 +792,7 @@ namespace dr570 { // dr570: dup 633
// expected-note@#dr570-r {{previous definition is here}}
}
-namespace dr571 { // dr571 unknown
- // FIXME: Add a codegen test.
- typedef int &ir;
- int n;
- // FIXME: Test if this has internal linkage.
- const ir r = n;
- // expected-warning@-1 {{'const' qualifier on reference type 'ir' (aka 'int &') has no effect}}
-}
+// dr571 is in dr571.cpp
namespace dr572 { // dr572: yes
enum E { a = 1, b = 2 };
diff --git a/clang/www/cxx_dr_status.html b/clang/www/cxx_dr_status.html
index 774c71bc1cb6b7..503472a2cae4eb 100755
--- a/clang/www/cxx_dr_status.html
+++ b/clang/www/cxx_dr_status.html
@@ -3154,7 +3154,7 @@ <h2 id="cxxdr">C++ defect report implementation status</h2>
<td><a href="https://cplusplus.github.io/CWG/issues/519.html">519</a></td>
<td>CD1</td>
<td>Null pointer preservation in <TT>void*</TT> conversions</td>
- <td class="full" align="center">Yes</td>
+ <td class="full" align="center">Clang 2.7</td>
</tr>
<tr id="520">
<td><a href="https://cplusplus.github.io/CWG/issues/520.html">520</a></td>
@@ -3468,7 +3468,7 @@ <h2 id="cxxdr">C++ defect report implementation status</h2>
<td><a href="https://cplusplus.github.io/CWG/issues/571.html">571</a></td>
<td>CD2</td>
<td>References declared <TT>const</TT></td>
- <td class="unknown" align="center">Unknown</td>
+ <td class="full" align="center">Clang 2.7</td>
</tr>
<tr id="572">
<td><a href="https://cplusplus.github.io/CWG/issues/572.html">572</a></td>
|
erichkeane
reviewed
Mar 7, 2024
| // Entities have external linkage by default. | ||
|
|
||
| // CHECK: @dr571::r = constant ptr @dr571::n | ||
| // CHECK: @dr571::r2 = constant ptr @dr571::n |
There was a problem hiding this comment.
These are showing up as 'dso_local' here: https://godbolt.org/z/Mcxz9c7PG
It isn't clear to me why, or really what it means semantically (https://llvm.org/docs/LangRef.html#runtime-preemption-specifiers).
There was a problem hiding this comment.
According to https://llvm.org/docs/LangRef.html#linkage-types, entities with no linkage specified are external, and that's what matters in this test, as it has direct correspondence to linkage the Standard speaks of.
I'm not sure what do we need to pass to -cc1 to make dso_local appear as it does on CE, but my understanding that if you load your dynamic library multiple times into the same process, each would maintain its own set of dso_local entities. So it's like internal linkage, but on dynamic linker level. Which doesn't seem interesting for this test.
erichkeane
approved these changes
Mar 7, 2024
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This patch covers
CWG519 "Null pointer preservation in
void*conversions",CWG571 "References declared const".