From 49dcb0f9ec865fd5474e5b552723adab2d7bf840 Mon Sep 17 00:00:00 2001
From: Dan Gohman <gohman@apple.com>
Date: Wed, 7 Jul 2010 23:52:58 +0000
Subject: [PATCH] Don't forward-declare registers for static allocas, which
 we'll prefer to materialize as local constants. This fixes the clang
 bootstrap abort.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107840 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/SelectionDAG/FastISel.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/CodeGen/SelectionDAG/FastISel.cpp b/lib/CodeGen/SelectionDAG/FastISel.cpp
index 5a245122775..5b566f675fe 100644
--- a/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -120,7 +120,9 @@ unsigned FastISel::getRegForValue(const Value *V) {
 
   // In bottom-up mode, just create the virtual register which will be used
   // to hold the value. It will be materialized later.
-  if (isa<Instruction>(V)) {
+  if (isa<Instruction>(V) &&
+      (!isa<AllocaInst>(V) ||
+       !FuncInfo.StaticAllocaMap.count(cast<AllocaInst>(V)))) {
     Reg = createResultReg(TLI.getRegClassFor(VT));
     FuncInfo.ValueMap[V] = Reg;
     return Reg;