Hal Finkel 4e703f82f2 [PowerPC] Add a DAGToDAG peephole to remove unnecessary zero-exts ... On PPC64, we end up with lots of i32 -> i64 zero extensions, not only from all of the usual places, but also from the ABI, which specifies that values passed are zero extended. Almost all 32-bit PPC instructions in PPC64 mode are defined to do *something* to the higher-order bits, and for some instructions, that action clears those bits (thus providing a zero-extended result). This is especially common after rotate-and-mask instructions. Adding an additional instruction to zero-extend the results of these instructions is unnecessary. This PPCISelDAGToDAG peephole optimization examines these zero-extensions, and looks back through their operands to see if all instructions will implicitly zero extend their results. If so, we convert these instructions to their 64-bit variants (which is an internal change only, the actual encoding of these instructions is the same as the original 32-bit ones) and remove the unnecessary zero-extension (changing where the INSERT_SUBREG instructions are to make everything internally consistent). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224169 91177308-0d34-0410-b5e6-96231b3b80d8		2014-12-12 23:59:36 +00:00
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Analysis	ValueTracking: Don't recurse too deeply in computeKnownBitsFromAssume	2014-12-12 23:59:29 +00:00
AsmParser
Bitcode	Bitcode: Add missing "Remove in 4.0" comments	2014-12-12 02:11:31 +00:00
CodeGen	Reapply "[MachineScheduler] Fix for PR21807: minor code difference building with/without -g."	2014-12-12 15:09:58 +00:00
DebugInfo
ExecutionEngine
IR	IR: Don't track nullptr on metadata RAUW	2014-12-12 19:24:33 +00:00
IRReader
LineEditor
Linker
LTO
MC	Clean up static analyzer warnings.	2014-12-12 21:48:03 +00:00
Object
Option
ProfileData
Support	Pass EC by reference to MemoryBufferMMapFile to return error code.	2014-12-12 22:27:53 +00:00
TableGen	Clean up static analyzer warnings.	2014-12-12 21:48:03 +00:00
Target	[PowerPC] Add a DAGToDAG peephole to remove unnecessary zero-exts	2014-12-12 23:59:36 +00:00
Transforms	More code format fix from r224133, NFC	2014-12-12 18:48:37 +00:00
CMakeLists.txt
LLVMBuild.txt
Makefile