llvm-c: Introduce 'LLVMDISubprogramReplaceType'

[davidgmbb]

The C API does not provide a way to replace the subroutine type after creating a subprogram. This functionality is useful for creating a subroutine type composed of types which have the subprogram as scope

[llvmbot]

@llvm/pr-subscribers-llvm-ir

@llvm/pr-subscribers-debuginfo

Author: David (davidgmbb)

Changes

The C API does not provide a way to replace the subroutine type after creating a subprogram. This functionality is useful for creating a subroutine type composed of types which have the subprogram as scope

---

Full diff: https://github.com/llvm/llvm-project/pull/143461.diff

2 Files Affected:

• (modified) llvm/include/llvm-c/DebugInfo.h (+9)
• (modified) llvm/lib/IR/DebugInfo.cpp (+4)

diff --git a/llvm/include/llvm-c/DebugInfo.h b/llvm/include/llvm-c/DebugInfo.h
index 991def64028da..bffed4bebbda6 100644
--- a/llvm/include/llvm-c/DebugInfo.h
+++ b/llvm/include/llvm-c/DebugInfo.h
@@ -1420,6 +1420,15 @@ void LLVMSetSubprogram(LLVMValueRef Func, LLVMMetadataRef SP);
  */
 unsigned LLVMDISubprogramGetLine(LLVMMetadataRef Subprogram);
 
+/**
+ * Replace the subprogram subroutine type
+ * \param Subprogram        The subprogram object.
+ * \param SubroutineType    The new subroutine type
+ *
+ * @see DISubprogram::replaceType()
+ */
+void LLVMDISubprogramReplaceType(LLVMMetadataRef Subprogram, LLVMMetadataRef SubroutineType);
+
 /**
  * Get the debug location for the given instruction.
  *
diff --git a/llvm/lib/IR/DebugInfo.cpp b/llvm/lib/IR/DebugInfo.cpp
index 7db9891fdbd75..c26dfcde87edf 100644
--- a/llvm/lib/IR/DebugInfo.cpp
+++ b/llvm/lib/IR/DebugInfo.cpp
@@ -1818,6 +1818,10 @@ unsigned LLVMDISubprogramGetLine(LLVMMetadataRef Subprogram) {
   return unwrapDI<DISubprogram>(Subprogram)->getLine();
 }
 
+void LLVMDISubprogramReplaceType(LLVMMetadataRef Subprogram, LLVMMetadataRef SubroutineType) {
+  unwrapDI<DISubprogram>(Subprogram)->replaceType(unwrapDI<DISubroutineType>(SubroutineType));
+}
+
 LLVMMetadataRef LLVMInstructionGetDebugLoc(LLVMValueRef Inst) {
   return wrap(unwrap<Instruction>(Inst)->getDebugLoc().getAsMDNode());
 }

[github-actions]

✅ With the latest revision this PR passed the C/C++ code formatter.

[davidgmbb]

ping

[dwblaikie]

Do we have unit test coverage for other parts of the debug info C API? If so, could you add some for this function too?

[davidgmbb]

Do we have unit test coverage for other parts of the debug info C API? If so, could you add some for this function too?

Hi. Thanks for taking some time to review the PR. I found some tests and added a call to the new function there, but I don't know if they are automatically triggered in CI runs.

[OCHyams]

Do we have unit test coverage for other parts of the debug info C API? If so, could you add some for this function too?

Hi. Thanks for taking some time to review the PR. I found some tests and added a call to the new function there, but I don't know if they are automatically triggered in CI runs.

If you build llvm-c-test (e.g. build-dir> ninja llvm-c-test) you can run that specific test with lit llvm-dir> llvm-lit llvm/test/Bindings/llvm-c/debug_info_new_format.ll. I believe it runs as part of ninja check-llvm and therefor IIUC should be run in the pre-merge checks.

[davidgmbb]

Do we have unit test coverage for other parts of the debug info C API? If so, could you add some for this function too?

Hi. Thanks for taking some time to review the PR. I found some tests and added a call to the new function there, but I don't know if they are automatically triggered in CI runs.

If you build llvm-c-test (e.g. build-dir> ninja llvm-c-test) you can run that specific test with lit llvm-dir> llvm-lit llvm/test/Bindings/llvm-c/debug_info_new_format.ll. I believe it runs as part of ninja check-llvm and therefor IIUC should be run in the pre-merge checks.

Thanks for the explanation. I checked the logs and that test passed. I am running all the tests locally but I have an old cheap CPU and it's taking forever. If I run just that test it passes.

[OCHyams]

The test update LGTM. If @dwblaikie has no further comments, I can merge this for you if you don't have commit access?