From d2e985fd323c167e20f77b045a1d99ad166e65db Mon Sep 17 00:00:00 2001
From: rdivacky <rdivacky@FreeBSD.org>
Date: Wed, 18 Nov 2009 14:58:34 +0000
Subject: Update LLVM to r89205.
---
lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 30 ++++++++++++------------------
1 file changed, 12 insertions(+), 18 deletions(-)
(limited to 'lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 5f70cb8..06ffdd6 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -37,7 +37,6 @@
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
-#include <set>
using namespace llvm;
STATISTIC(NodesCombined , "Number of dag nodes combined");
@@ -4443,14 +4442,13 @@ SDValue DAGCombiner::visitBRCOND(SDNode *N) {
SDValue Chain = N->getOperand(0);
SDValue N1 = N->getOperand(1);
SDValue N2 = N->getOperand(2);
- ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
- // never taken branch, fold to chain
- if (N1C && N1C->isNullValue())
- return Chain;
- // unconditional branch
- if (N1C && N1C->getAPIntValue() == 1)
- return DAG.getNode(ISD::BR, N->getDebugLoc(), MVT::Other, Chain, N2);
+ // If N is a constant we could fold this into a fallthrough or unconditional
+ // branch. However that doesn't happen very often in normal code, because
+ // Instcombine/SimplifyCFG should have handled the available opportunities.
+ // If we did this folding here, it would be necessary to update the
+ // MachineBasicBlock CFG, which is awkward.
+
// fold a brcond with a setcc condition into a BR_CC node if BR_CC is legal
// on the target.
if (N1.getOpcode() == ISD::SETCC &&
@@ -4517,22 +4515,18 @@ SDValue DAGCombiner::visitBR_CC(SDNode *N) {
CondCodeSDNode *CC = cast<CondCodeSDNode>(N->getOperand(1));
SDValue CondLHS = N->getOperand(2), CondRHS = N->getOperand(3);
+ // If N is a constant we could fold this into a fallthrough or unconditional
+ // branch. However that doesn't happen very often in normal code, because
+ // Instcombine/SimplifyCFG should have handled the available opportunities.
+ // If we did this folding here, it would be necessary to update the
+ // MachineBasicBlock CFG, which is awkward.
+
// Use SimplifySetCC to simplify SETCC's.
SDValue Simp = SimplifySetCC(TLI.getSetCCResultType(CondLHS.getValueType()),
CondLHS, CondRHS, CC->get(), N->getDebugLoc(),
false);
if (Simp.getNode()) AddToWorkList(Simp.getNode());
- ConstantSDNode *SCCC = dyn_cast_or_null<ConstantSDNode>(Simp.getNode());
-
- // fold br_cc true, dest -> br dest (unconditional branch)
- if (SCCC && !SCCC->isNullValue())
- return DAG.getNode(ISD::BR, N->getDebugLoc(), MVT::Other,
- N->getOperand(0), N->getOperand(4));
- // fold br_cc false, dest -> unconditional fall through
- if (SCCC && SCCC->isNullValue())
- return N->getOperand(0);
-
// fold to a simpler setcc
if (Simp.getNode() && Simp.getOpcode() == ISD::SETCC)
return DAG.getNode(ISD::BR_CC, N->getDebugLoc(), MVT::Other,
--
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