Fix a bug I noticed by inspection: if the first instruction in the inlined

function was not an alloca, we wouldn't check the entry block for any allocas,
leading to increased stack space in some cases.  In practice, allocas are almost
always at the top of the block, so this was never noticed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25280 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 3 insertions, 5 deletions

diff --git a/lib/Transforms/Utils/InlineFunction.cpp b/lib/Transforms/Utils/InlineFunction.cpp
index cf45633447..40d02ab4bc 100644
--- a/lib/Transforms/Utils/InlineFunction.cpp
+++ b/lib/Transforms/Utils/InlineFunction.cpp
@@ -10,9 +10,6 @@
 // This file implements inlining of a function into a call site, resolving
 // parameters and the return value as appropriate.
 //
-// FIXME: This pass should transform alloca instructions in the called function
-// into alloca/dealloca pairs!  Or perhaps it should refuse to inline them!
-//
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Transforms/Utils/Cloning.h"
@@ -87,13 +84,14 @@ bool llvm::InlineFunction(CallSite CS) {
   // calculate which instruction they should be inserted before.  We insert the
   // instructions at the end of the current alloca list.
   //
-  if (isa<AllocaInst>(FirstNewBlock->begin())) {
+  {
     BasicBlock::iterator InsertPoint = Caller->begin()->begin();
     for (BasicBlock::iterator I = FirstNewBlock->begin(),
            E = FirstNewBlock->end(); I != E; )
       if (AllocaInst *AI = dyn_cast<AllocaInst>(I++))
         if (isa<Constant>(AI->getArraySize())) {
-          // Scan for the block of allocas that we can move over.
+          // Scan for the block of allocas that we can move over, and move them
+          // all at once.
           while (isa<AllocaInst>(I) &&
                  isa<Constant>(cast<AllocaInst>(I)->getArraySize()))
             ++I;