Chandler Carruth 63974b2144 Initial CodeGen support for CTTZ/CTLZ where a zero input produces an ... undefined result. This adds new ISD nodes for the new semantics, selecting them when the LLVM intrinsic indicates that the undef behavior is desired. The new nodes expand trivially to the old nodes, so targets don't actually need to do anything to support these new nodes besides indicating that they should be expanded. I've done this for all the operand types that I could figure out for all the targets. Owners of various targets, please review and let me know if any of these are incorrect. Note that the expand behavior is *conservatively correct*, and exactly matches LLVM's current behavior with these operations. Ideally this patch will not change behavior in any way. For example the regtest suite finds the exact same instruction sequences coming out of the code generator. That's why there are no new tests here -- all of this is being exercised by the existing test suite. Thanks to Duncan Sands for reviewing the various bits of this patch and helping me get the wrinkles ironed out with expanding for each target. Also thanks to Chris for clarifying through all the discussions that this is indeed the approach he was looking for. That said, there are likely still rough spots. Further review much appreciated. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146466 91177308-0d34-0410-b5e6-96231b3b80d8		2011-12-13 01:56:10 +00:00
..
Mangler.h	Remove std::string version of getNameWithPrefix.	2011-02-11 05:23:09 +00:00
Target.td	Extend AsmMatcher token literal matching to allow aliasing.	2011-12-06 23:43:54 +00:00
TargetCallingConv.h	Minimize #include's and forward-declares in Target.	2011-12-10 22:35:47 +00:00
TargetCallingConv.td
TargetData.h	Haven't yet found a nice way to handle TargetData verification in the	2011-10-20 19:24:44 +00:00
TargetELFWriterInfo.h
TargetFrameLowering.h	Emit segmented-stack specific code into function prologues for	2011-08-30 19:39:58 +00:00
TargetInstrInfo.h	Move isUnpredicatedTerminator() default implementation to TargetInstrInfoImpl to break Target's dependency on CodeGen.	2011-12-09 06:41:08 +00:00
TargetIntrinsicInfo.h	land David Blaikie's patch to de-constify Type, with a few tweaks.	2011-07-18 04:54:35 +00:00
TargetJITInfo.h	Merge System into Support.	2010-11-29 18:16:10 +00:00
TargetLibraryInfo.h	Enhance both TargetLibraryInfo and SelectionDAGBuilder so that the latter can use the former to prevent the formation of libm SDNode's when -fno-builtin is passed.	2011-12-08 22:15:21 +00:00
TargetLowering.h	Minimize #include's and forward-declares in Target.	2011-12-10 22:35:47 +00:00
TargetLoweringObjectFile.h	Goodbye TargetAsmInfo. This eliminate last bit of CodeGen and Target in llvm-mc.	2011-07-20 19:50:42 +00:00
TargetMachine.h	Move global variables in TargetMachine into new TargetOptions class. As an API	2011-12-02 22:16:29 +00:00
TargetOpcodes.h	First chunk of MachineInstr bundle support.	2011-12-06 22:12:01 +00:00
TargetOptions.h	Move global variables in TargetMachine into new TargetOptions class. As an API	2011-12-02 22:16:29 +00:00
TargetRegisterInfo.h	Remove the TRI::getSubRegisterRegClass() hook.	2011-10-06 00:08:27 +00:00
TargetSchedule.td
TargetSelectionDAG.td	Initial CodeGen support for CTTZ/CTLZ where a zero input produces an	2011-12-13 01:56:10 +00:00
TargetSelectionDAGInfo.h
TargetSubtargetInfo.h	Rename TargetSubtarget to TargetSubtargetInfo for consistency.	2011-07-01 21:01:15 +00:00