From b1515fe52270506faf1cff3184606cf76ace892b Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Tue, 29 Mar 2005 06:37:47 +0000
Subject: [PATCH] disable this transformation in the one obscure case that
 really pessimizes pointer analysis.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@20916 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Transforms/Scalar/InstructionCombining.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index e944672d262..40088ba06be 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -4646,6 +4646,9 @@ static Instruction *InstCombineLoadCast(InstCombiner &IC, LoadInst &LI) {
           }
 
       if ((SrcPTy->isInteger() || isa<PointerType>(SrcPTy)) &&
+          // Do not allow turning this into a load of an integer, which is then
+          // casted to a pointer, this pessimizes pointer analysis a lot.
+          (isa<PointerType>(SrcPTy) == isa<PointerType>(LI.getType())) &&
           IC.getTargetData().getTypeSize(SrcPTy) == 
                IC.getTargetData().getTypeSize(DestPTy)) {