From: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Date: Fri, 22 Mar 2013 14:58:17 +0000 (+0000)
Subject: Tighten iaddroff ComplexPattern.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0301e79a1af665422f205fd367cdbd8e6164f324;p=oota-llvm.git

Tighten iaddroff ComplexPattern.

The iaddroff ComplexPattern is supposed to recognize displacement
expressions that have been processed by a SelectAddressRegImm,
which means it needs to accept TargetConstant and TargetGlobalAddress
nodes.  Currently, it erroneously also accepts some other nodes,
in particular Constant and PPCISD::Lo.

While this problem is currently latent, it would cause wrong-code
bugs with a follow-on patch I'm about to commit, so this patch
tightens the ComplexPattern.  The equivalent change is made in
PPCDAGToDAGISel::Select, where pre-inc load patterns are handled
(as opposed to store patterns, the loads are handled in C++ code
without making use of the .td ComplexPattern).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177732 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
index a2a0f2e3de3..926859a6a3d 100644
--- a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
+++ b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
@@ -120,10 +120,10 @@ namespace {
     }
 
     /// SelectAddrImmOffs - Return true if the operand is valid for a preinc
-    /// immediate field.  Because preinc imms have already been validated, just
-    /// accept it.
+    /// immediate field.  Note that the operand at this point is already the
+    /// result of a prior SelectAddressRegImm call.
     bool SelectAddrImmOffs(SDValue N, SDValue &Out) const {
-      if (isa<ConstantSDNode>(N) || N.getOpcode() == PPCISD::Lo ||
+      if (N.getOpcode() == ISD::TargetConstant ||
           N.getOpcode() == ISD::TargetGlobalAddress) {
         Out = N;
         return true;
@@ -1044,7 +1044,7 @@ SDNode *PPCDAGToDAGISel::Select(SDNode *N) {
       break;
 
     SDValue Offset = LD->getOffset();
-    if (isa<ConstantSDNode>(Offset) ||
+    if (Offset.getOpcode() == ISD::TargetConstant ||
         Offset.getOpcode() == ISD::TargetGlobalAddress) {
 
       unsigned Opcode;