[clang] 5c268cf - [Clang] Extend EmitPseudoVariable to support debug records (#94956)

[via cfe-commits]

Author: Stephen Tozer
Date: 2024-06-10T11:57:53+01:00
New Revision: 5c268cfaae521dc2db1af58085e3c8d66a5533fe

URL: https://github.com/llvm/llvm-project/commit/5c268cfaae521dc2db1af58085e3c8d66a5533fe
DIFF: https://github.com/llvm/llvm-project/commit/5c268cfaae521dc2db1af58085e3c8d66a5533fe.diff

LOG: [Clang] Extend EmitPseudoVariable to support debug records (#94956)

CGDebugInfo::EmitPseudoVariable currently uses detailed logic to exactly
collect llvm.dbg.declare users of an alloca. This patch replaces this
with an LLVM function for finding debug declares intrinsics and also
adds the same for debug records, simplifying the code and adding record
support.

No tests added in this commit because it is NFC for intrinsics, and
there is no way to make clang emit records directly yet - one of the
existing tests however will switch to covering debug records once
https://github.com/llvm/llvm-project/pull/89799 relands.

Added: 
    

Modified: 
    clang/lib/CodeGen/CGDebugInfo.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 681a475f9e4be..11e2d549d8a45 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -5766,28 +5766,16 @@ void CGDebugInfo::EmitPseudoVariable(CGBuilderTy &Builder,
   // it is loaded upon use, so we identify such pattern here.
   if (llvm::LoadInst *Load = dyn_cast<llvm::LoadInst>(Value)) {
     llvm::Value *Var = Load->getPointerOperand();
-    if (llvm::Metadata *MDValue = llvm::ValueAsMetadata::getIfExists(Var)) {
-      if (llvm::Value *DbgValue = llvm::MetadataAsValue::getIfExists(
-              CGM.getLLVMContext(), MDValue)) {
-        for (llvm::User *U : DbgValue->users()) {
-          if (llvm::CallInst *DbgDeclare = dyn_cast<llvm::CallInst>(U)) {
-            if (DbgDeclare->getCalledFunction()->getIntrinsicID() ==
-                    llvm::Intrinsic::dbg_declare &&
-                DbgDeclare->getArgOperand(0) == DbgValue) {
-              // There can be implicit type cast applied on a variable if it is
-              // an opaque ptr, in this case its debug info may not match the
-              // actual type of object being used as in the next instruction, so
-              // we will need to emit a pseudo variable for type-casted value.
-              llvm::DILocalVariable *MDNode = cast<llvm::DILocalVariable>(
-                  cast<llvm::MetadataAsValue>(DbgDeclare->getOperand(1))
-                      ->getMetadata());
-              if (MDNode->getType() == Type)
-                return;
-            }
-          }
-        }
-      }
-    }
+    // There can be implicit type cast applied on a variable if it is an opaque
+    // ptr, in this case its debug info may not match the actual type of object
+    // being used as in the next instruction, so we will need to emit a pseudo
+    // variable for type-casted value.
+    auto DeclareTypeMatches = [&](auto *DbgDeclare) {
+      return DbgDeclare->getVariable()->getType() == Type;
+    };
+    if (any_of(llvm::findDbgDeclares(Var), DeclareTypeMatches) ||
+        any_of(llvm::findDVRDeclares(Var), DeclareTypeMatches))
+      return;
   }
 
   // Find the correct location to insert a sequence of instructions to