From: Tim Northover <Tim.Northover@arm.com>
Date: Tue, 26 Jun 2012 18:46:28 +0000 (+0000)
Subject: Teach TableGen to put chains on more instructions
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=ca578e7ba6b1e4ce955134e3fb1d5014942e5248;p=oota-llvm.git

Teach TableGen to put chains on more instructions

When generating selection tables for Pat instances, TableGen relied on
an output Instruction's Pattern field being set to infer whether a
chain should be added.

This patch adds additional logic to check various flag fields so that
correct code can be generated even if Pattern is unset.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159217 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/utils/TableGen/DAGISelMatcherGen.cpp b/utils/TableGen/DAGISelMatcherGen.cpp
index 2ac7b87e701..aed222c0949 100644
--- a/utils/TableGen/DAGISelMatcherGen.cpp
+++ b/utils/TableGen/DAGISelMatcherGen.cpp
@@ -690,6 +690,13 @@ EmitResultInstructionAsOperand(const TreePatternNode *N,
   bool NodeHasChain = InstPatNode &&
                       InstPatNode->TreeHasProperty(SDNPHasChain, CGP);
 
+  // Instructions which load and store from memory should have a chain,
+  // regardless of whether they happen to have an internal pattern saying so.
+  if (Pattern.getSrcPattern()->TreeHasProperty(SDNPHasChain, CGP)
+      && (II.hasCtrlDep || II.mayLoad || II.mayStore || II.canFoldAsLoad ||
+          II.hasSideEffects))
+      NodeHasChain = true;
+
   bool isRoot = N == Pattern.getDstPattern();
 
   // TreeHasOutGlue - True if this tree has glue.