name change: isPow2DivCheap -> isPow2SDivCheap

isPow2DivCheap

That name doesn't specify signed or unsigned.

Lazy as I am, I eventually read the function and variable comments. It turns out that this is strictly about signed div. But I discovered that the comments are wrong:

   srl/add/sra

is not the general sequence for signed integer division by power-of-2. We need one more 'sra':

   sra/srl/add/sra

That's the sequence produced in DAGCombiner. The first 'sra' may be removed when dividing by exactly '2', but that's a special case.

This patch corrects the comments, changes the name of the flag bit, and changes the name of the accessor methods.

No functional change intended.

Differential Revision: http://reviews.llvm.org/D5010

llvm-svn: 216237

4 files changed, 4 insertions, 4 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 5fd9bf39e0e..a74afe1228e 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -2082,7 +2082,7 @@ SDValue DAGCombiner::visitSDIV(SDNode *N) {
                                      (-N1C->getAPIntValue()).isPowerOf2())) {
     // If dividing by powers of two is cheap, then don't perform the following
     // fold.
-    if (TLI.isPow2DivCheap())
+    if (TLI.isPow2SDivCheap())
       return SDValue();
 
     // Target-specific implementation of sdiv x, pow2.
diff --git a/llvm/lib/CodeGen/TargetLoweringBase.cpp b/llvm/lib/CodeGen/TargetLoweringBase.cpp
index f7686506c23..11b65715de7 100644
--- a/llvm/lib/CodeGen/TargetLoweringBase.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringBase.cpp
@@ -701,7 +701,7 @@ TargetLoweringBase::TargetLoweringBase(const TargetMachine &tm,
   HasMultipleConditionRegisters = false;
   HasExtractBitsInsn = false;
   IntDivIsCheap = false;
-  Pow2DivIsCheap = false;
+  Pow2SDivIsCheap = false;
   JumpIsExpensive = false;
   PredictableSelectIsExpensive = false;
   MaskAndBranchFoldingIsLegal = false;
diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index 3badab60aa1..ebf691065c9 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -67,7 +67,7 @@ static TargetLoweringObjectFile *createTLOF(const Triple &TT) {
 PPCTargetLowering::PPCTargetLowering(PPCTargetMachine &TM)
     : TargetLowering(TM, createTLOF(Triple(TM.getTargetTriple()))),
       Subtarget(*TM.getSubtargetImpl()) {
-  setPow2DivIsCheap();
+  setPow2SDivIsCheap();
 
   // Use _setjmp/_longjmp instead of setjmp/longjmp.
   setUseUnderscoreSetJmp(true);
diff --git a/llvm/lib/Target/R600/AMDGPUISelLowering.cpp b/llvm/lib/Target/R600/AMDGPUISelLowering.cpp
index 7d4aadcc5ca..9f22239556e 100644
--- a/llvm/lib/Target/R600/AMDGPUISelLowering.cpp
+++ b/llvm/lib/Target/R600/AMDGPUISelLowering.cpp
@@ -386,7 +386,7 @@ AMDGPUTargetLowering::AMDGPUTargetLowering(TargetMachine &TM) :
   // There are no integer divide instructions, and these expand to a pretty
   // large sequence of instructions.
   setIntDivIsCheap(false);
-  setPow2DivIsCheap(false);
+  setPow2SDivIsCheap(false);
 
   // TODO: Investigate this when 64-bit divides are implemented.
   addBypassSlowDiv(64, 32);