[llvm] r177732 - Tighten iaddroff ComplexPattern.

[Ulrich Weigand]

Author: uweigand
Date: Fri Mar 22 09:58:17 2013
New Revision: 177732

URL: http://llvm.org/viewvc/llvm-project?rev=177732&view=rev
Log:
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).


Modified:
    llvm/trunk/lib/Target/PowerPC/PPCISelDAGToDAG.cpp

Modified: llvm/trunk/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCISelDAGToDAG.cpp?rev=177732&r1=177731&r2=177732&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCISelDAGToDAG.cpp (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCISelDAGToDAG.cpp Fri Mar 22 09:58:17 2013
@@ -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 *
       break;
 
     SDValue Offset = LD->getOffset();
-    if (isa<ConstantSDNode>(Offset) ||
+    if (Offset.getOpcode() == ISD::TargetConstant ||
         Offset.getOpcode() == ISD::TargetGlobalAddress) {
 
       unsigned Opcode;