Jakob Stoklund Olesen 976647d95d Make calls scheduling boundaries post-ra. ... Before register allocation, instructions can be moved across calls in order to reduce register pressure. After register allocation, we don't gain a lot by moving callee-saved defs across calls. In fact, since the scheduler doesn't have a good idea how registers are used in the callee, it can't really make good scheduling decisions. This changes the schedule in two ways: 1. Latencies to call uses and defs are no longer accounted for, causing some random shuffling around calls. This isn't really a problem since those uses and defs are inaccurate proxies for what happens inside the callee. They don't represent registers used by the call instruction itself. 2. Instructions are no longer moved across calls. This didn't happen very often, and the scheduling decision was made on dubious information anyway. As with any scheduling change, benchmark numbers shift around a bit, but there is no positive or negative trend from this change. This makes the post-ra scheduler 5% faster for ARM targets. The secret motivation for this patch is the introduction of register mask operands representing call clobbers. The most efficient way of handling regmasks in ScheduleDAGInstrs is to model them as barriers for physreg live ranges, but not for virtreg live ranges. That's fine pre-ra, but post-ra it would have the same effect as this patch. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151265 91177308-0d34-0410-b5e6-96231b3b80d8		2012-02-23 17:54:21 +00:00
..
Analysis	Fix typo.	2012-02-23 05:38:51 +00:00
Archive	Avoid using an invalidated iterator.	2012-01-23 05:07:16 +00:00
AsmParser	Convert assert(0) to llvm_unreachable	2012-02-07 05:05:23 +00:00
Bitcode	Enable streaming of bitcode	2012-02-06 22:30:29 +00:00
CodeGen	Make calls scheduling boundaries post-ra.	2012-02-23 17:54:21 +00:00
DebugInfo	More dead code removal (using -Wunreachable-code)	2012-01-20 21:51:11 +00:00
ExecutionEngine	Remove dead code. Improve llvm_unreachable text. Simplify some control flow.	2012-02-19 11:37:01 +00:00
Linker	Capitalize messages so that they appear nicely with the linker's error messages.	2012-02-14 09:13:54 +00:00
MC	MC: Fix the MCNullStreamer which was broken in r147763.	2012-02-22 23:49:50 +00:00
Object	Remove static ctor.	2012-02-22 13:42:11 +00:00
Support	Update for the removal of Hashing.cpp.	2012-02-23 09:33:44 +00:00
TableGen	Add Foreach Loop	2012-02-22 16:09:41 +00:00
Target	Remove unused variable.	2012-02-23 11:01:22 +00:00
Transforms	Reflow code, no functionality change.	2012-02-23 17:42:19 +00:00
VMCore	Reinstate r151049 now that GeneralHash is fixed.	2012-02-23 09:17:40 +00:00
CMakeLists.txt	Move TableGen's parser and entry point into a library	2011-10-01 16:41:13 +00:00
LLVMBuild.txt	LLVMBuild: Introduce a common section which currently has a list of the	2011-12-12 22:45:54 +00:00
Makefile	Remove more of llvmc and dependencies.	2011-09-20 00:34:27 +00:00