[CFE][Codegen] Make sure to maintain the contiguity of all the static allocas

at the start of the entry block, which in turn would aid better code transformation/optimization.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D110257

1 files changed, 8 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index c3c2899..d87cf2d 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -424,6 +424,14 @@ void CodeGenFunction::FinishFunction(SourceLocation EndLoc) {
   AllocaInsertPt = nullptr;
   Ptr->eraseFromParent();
 
+  // PostAllocaInsertPt, if created, was lazily created when it was required,
+  // remove it now since it was just created for our own convenience.
+  if (PostAllocaInsertPt) {
+    llvm::Instruction *PostPtr = PostAllocaInsertPt;
+    PostAllocaInsertPt = nullptr;
+    PostPtr->eraseFromParent();
+  }
+
   // If someone took the address of a label but never did an indirect goto, we
   // made a zero entry PHI node, which is illegal, zap it now.
   if (IndirectBranch) {