Chris Lattner 87f1ce9b96 This changes the PromoteMemToReg function to create "pruned" SSA form, not ... "minimal" SSA form (in other words, it doesn't insert dead PHIs). This speeds up the mem2reg pass very significantly because it doesn't have to do a lot of frivolous work in many common cases. In the 252.eon function I have been playing with, this doesn't even insert the 120 PHI nodes that it used to which were trivially dead (in the process of promoting 356 alloca instructions overall). This speeds up the mem2reg pass from 1.2459s to 0.1284s. More significantly, the DCE pass used to take 2.4138s to remove the 120 dead PHI nodes that mem2reg constructed, now it takes 0.0134s (which is the time to scan the function and decide that there is nothing dead). So overall, on this one function, we speed things up a total of 3.5179s, which is a 24.8x speedup! :) This change is tested by the Mem2Reg/2003-10-05-DeadPHIInsertion.ll test, which now passes. llvm-svn: 8884		2003-10-05 22:19:20 +00:00
..
BasicBlockUtils.cpp	Spell `necessary' correctly.	2003-08-18 14:43:39 +00:00
BreakCriticalEdges.cpp	Remove unnecesary &*'s	2003-04-23 16:37:45 +00:00
CloneFunction.cpp	Refactor CloneFunction to expose the new CloneBasicBlock function	2003-04-18 03:50:09 +00:00
CloneModule.cpp	Make sure that the cloned module retains the type symbol table entries!	2003-04-24 17:15:33 +00:00
CloneTrace.cpp	Fixed comment width, changed arg to be const, fixed indentation, removed unnecessary includes.	2003-05-31 20:01:37 +00:00
DemoteRegToStack.cpp	Minor cleanups, no functional changes	2003-09-20 14:36:23 +00:00
InlineFunction.cpp	Fix bugs in the last change	2003-09-22 23:30:59 +00:00
Linker.cpp	Fix bug where we considered function types equivalent even if they had differing numbers of arguments	2003-08-28 16:42:50 +00:00
Local.cpp	Implement SimplifyCFG/2003-08-17-FoldSwitch.ll:test5	2003-08-23 23:18:19 +00:00
Makefile	*** empty log message ***	2002-07-23 17:52:38 +00:00
PromoteMemoryToRegister.cpp	This changes the PromoteMemToReg function to create "pruned" SSA form, not	2003-10-05 22:19:20 +00:00
SimplifyCFG.cpp	Eliminate support for the llvm.unwind intrinisic, using the Unwind instruction instead	2003-09-08 19:44:26 +00:00
UnifyFunctionExitNodes.cpp	Expand the pass to unify all of the unwind blocks as well	2003-09-10 20:34:51 +00:00
ValueMapper.cpp	New const_cast instead of c style cast	2003-04-18 03:49:49 +00:00
ValueMapper.h	Initial checkin of Module cloning support stuff	2002-11-20 20:47:41 +00:00