Jakob Stoklund Olesen 7016cf66ee Allow <undef> flags on def operands as well as uses. ... The <undef> flag says that a MachineOperand doesn't read its register, or doesn't depend on the previous value of its register. A full register def never depends on the previous register value. A partial register def may depend on the previous value if it is intended to update part of a register. For example: %vreg10:dsub_0<def,undef> = COPY %vreg1 %vreg10:dsub_1<def> = COPY %vreg2 The first copy instruction defines the full %vreg10 register with the bits not covered by dsub_0 defined as <undef>. It is not considered a read of %vreg10. The second copy modifies part of %vreg10 while preserving the rest. It has an implicit read of %vreg10. This patch adds a MachineOperand::readsReg() method to determine if an operand reads its register. Previously, this was modelled by adding a full-register <imp-def> operand to the instruction. This approach makes it possible to determine directly from a MachineOperand if it reads its register. No scanning of MI operands is required. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141124 91177308-0d34-0410-b5e6-96231b3b80d8		2011-10-04 21:49:33 +00:00
..
Analysis	The product of two chrec's can always be represented as a chrec.	2011-10-04 06:51:26 +00:00
Archive	Rewrite the CMake build to use explicit dependencies between libraries,	2011-07-29 00:14:25 +00:00
AsmParser	Remove last references to hotpatch.	2011-10-04 03:08:43 +00:00
Bitcode	Fix a typo in the bitcode reader in the handling of atomic stores. Reported by David Meyer on llvmdev.	2011-09-19 19:41:28 +00:00
CodeGen	Allow <undef> flags on def operands as well as uses.	2011-10-04 21:49:33 +00:00
DebugInfo	DWARF: avoid unnecessary map lookups.	2011-09-21 17:31:42 +00:00
ExecutionEngine	MCJIT initialization TargetData	2011-09-30 16:40:10 +00:00
Linker	lib/Linker: add support of deps which does not end with ".so".	2011-09-20 22:52:35 +00:00
MC	Add definition of MipsELFObjectWriter.	2011-09-30 21:55:40 +00:00
Object	Object: Add isSection{Data,BSS}.	2011-09-28 20:57:30 +00:00
Support	Fix typo in comments.	2011-10-03 21:30:08 +00:00
TableGen	Replace snprintf with raw_string_ostream.	2011-10-04 21:08:56 +00:00
Target	Teach PPCInstrInfo to handle sub-classes.	2011-10-04 15:28:47 +00:00
Transforms	LSR should avoid redundant edge splitting.	2011-10-04 03:50:44 +00:00
VMCore	Unbreak CMake build.	2011-10-04 18:22:24 +00:00
CMakeLists.txt	Move TableGen's parser and entry point into a library	2011-10-01 16:41:13 +00:00
Makefile	Remove more of llvmc and dependencies.	2011-09-20 00:34:27 +00:00