Update optimization passes to handle inalloca arguments

Summary:
I searched Transforms/ and Analysis/ for 'ByVal' and updated those call
sites to check for inalloca if appropriate.

I added tests for any change that would allow an optimization to fire on
inalloca.

Reviewers: nlewycky

Differential Revision: http://llvm-reviews.chandlerc.com/D2449

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200281 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 1 deletions

diff --git a/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp b/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
index 4c861b3fd0..1f69176817 100644
--- a/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
+++ b/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
@@ -81,10 +81,14 @@ isOnlyCopiedFromConstantGlobal(Value *V, MemTransferInst *&TheCopy,
       if (CS.isCallee(UI))
         continue;
 
+      // Inalloca arguments are clobbered by the call.
+      unsigned ArgNo = CS.getArgumentNo(UI);
+      if (CS.isInAllocaArgument(ArgNo))
+        return false;
+
       // If this is a readonly/readnone call site, then we know it is just a
       // load (but one that potentially returns the value itself), so we can
       // ignore it if we know that the value isn't captured.
-      unsigned ArgNo = CS.getArgumentNo(UI);
       if (CS.onlyReadsMemory() &&
           (CS.getInstruction()->use_empty() || CS.doesNotCapture(ArgNo)))
         continue;