Commit Graph

4669 Commits

Author SHA1 Message Date
Chris Lattner
4f8c18c7c7 Eliminate the dropInstruction method, which is not needed any more.
Fix a subtle iterator invalidation bug I introduced in the last commit.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60258 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 23:30:39 +00:00
Chris Lattner
396a4a55e5 Change MemDep::getNonLocalDependency to return its results as
a smallvector instead of a DenseMap.  This speeds up GVN by 5%
on 403.gcc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60255 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 21:33:22 +00:00
Chris Lattner
86b29ef64a reimplement getNonLocalDependency with a simpler worklist
formulation that is faster and doesn't require nonLazyHelper.
Much less code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60253 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 21:22:42 +00:00
Chris Lattner
3a76be584b Fix a thinko that manifested as a crash on clamav last night.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60251 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 20:29:04 +00:00
Chris Lattner
5391a1d804 Split getDependency into getDependency and getDependencyFrom, the
former does caching, the later doesn't.  This dramatically simplifies
the logic in getDependency and getDependencyFrom.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60234 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 03:47:00 +00:00
Bill Wendling
411052bb96 Temporarily revert r60195. It's causing an optimized bootstrap of llvm-gcc to fail.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60233 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 03:43:04 +00:00
Chris Lattner
4c72400625 Introduce and use a new MemDepResult class to hold the results of a memdep
query.  This makes it crystal clear what cases can escape from MemDep that
the clients have to handle.  This also gives the clients a nice simplified
interface to it that is easy to poke at.

This patch also makes DepResultTy and MemoryDependenceAnalysis::DepType
private, yay.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60231 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 02:29:27 +00:00
Chris Lattner
39f372e23e Reimplement the internal abstraction used by MemDep in terms
of a pointer/int pair instead of a manually bitmangled pointer.
This forces clients to think a little more about checking the 
appropriate pieces and will be useful for internal 
implementation improvements later.

I'm not particularly happy with this.  After going through this
I don't think that the clients of memdep should be exposed to
the internal type at all.  I'll fix this in a subsequent commit.

This has no functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60230 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-29 01:43:36 +00:00
Chris Lattner
5425f22fa3 don't revisit instructions off the beginning of the block.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60221 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-28 22:50:08 +00:00
Chris Lattner
565f96b196 simplify some code, remove escaped newline.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60213 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-28 21:29:52 +00:00
Chris Lattner
f5102a0f08 don't call MergeBasicBlockIntoOnlyPred on a block whose only
predecessor is itself.  This doesn't make sense, and this is
a dead infinite loop anyway.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60210 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-28 19:54:49 +00:00
Chris Lattner
7605730ba8 rewrite RecursivelyDeleteTriviallyDeadInstructions to use a more efficient
formulation that doesn't require set lookups or scanning a set.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60203 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-28 01:20:46 +00:00
Chris Lattner
2872177834 remove some weirdness that came from the LSR code that has
nothing to do with dead instruction elimination.  No tests in
dejagnu depend on this, so I don't know what it was needed for.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60202 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-28 00:58:15 +00:00
Chris Lattner
925451e020 rewrite a big chunk of how DSE does recursive dead operand
elimination to use more modern infrastructure.  Also do a bunch
of small cleanups.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60201 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-28 00:27:14 +00:00
Chris Lattner
9fd4955c6a delete ErasePossiblyDeadInstructionTree, replacing uses of it with
RecursivelyDeleteTriviallyDeadInstructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60196 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 23:25:44 +00:00
Chris Lattner
1363949380 Simplify LoopStrengthReduce::DeleteTriviallyDeadInstructions by
making it use RecursivelyDeleteTriviallyDeadInstructions to do
the heavy lifting.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60195 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 23:23:35 +00:00
Chris Lattner
564c0a2330 enhance RecursivelyDeleteTriviallyDeadInstructions to make
PHIs dead if they are single-value.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60194 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 23:18:11 +00:00
Chris Lattner
4f02c74a8e Enhance RecursivelyDeleteTriviallyDeadInstructions to optionally
return a list of deleted instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60193 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 23:14:34 +00:00
Chris Lattner
a0d4486073 use continue to reduce indentation
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60192 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 23:00:20 +00:00
Chris Lattner
3481f24c06 remove doConstantPropagation and dceInstruction, they are just
wrappers around the interesting code and use an obscure iterator
abstraction that dates back many many years.

Move EraseDeadInstructions to Transforms/Utils and name it
RecursivelyDeleteTriviallyDeadInstructions.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60191 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 22:57:53 +00:00
Chris Lattner
15678533f3 simplify code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60190 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 22:56:14 +00:00
Chris Lattner
cb03f8547d simplify this logic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60189 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 22:46:09 +00:00
Nick Lewycky
8ca5248522 Chris prefers icmp/select over udiv!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60187 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 22:41:10 +00:00
Nick Lewycky
895f085385 Add a couple of missed optimizations on integer vectors. Multiply and divide
by 1, as well as multiply by -1.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60182 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 20:21:08 +00:00
Chris Lattner
9918fb5631 defensive patch: if CGP is merging a block with the entry block, make sure
it ends up being the entry block.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60180 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 19:29:14 +00:00
Chris Lattner
3d86d242c6 Fix PR3138: if we merge the entry block into another block, make sure to
move the other block back up into the entry position!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60179 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 19:25:19 +00:00
Chris Lattner
4aebaee0e4 switch InstCombine::visitLoadInst to use
FindAvailableLoadedValue


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60169 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 08:56:30 +00:00
Chris Lattner
ee6e10bc8e enhance FindAvailableLoadedValue to make use of AliasAnalysis
if it has it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60167 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 08:18:12 +00:00
Chris Lattner
52c95856b4 move FindAvailableLoadedValue from JumpThreading to Transforms/Utils.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60166 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 08:10:05 +00:00
Chris Lattner
5a5c9a5acd simplify this code a bit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60164 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 07:54:38 +00:00
Chris Lattner
3c4f8b91ef Use the new MergeBasicBlockIntoOnlyPred function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60163 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 07:54:12 +00:00
Chris Lattner
b29714a10a move MergeBasicBlockIntoOnlyPred to Transforms/Utils.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60162 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 07:43:12 +00:00
Chris Lattner
c7bcbf6903 rename ThreadBlock to ProcessBlock, since it does other things than
just simple threading.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60157 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 07:20:04 +00:00
Chris Lattner
69e067fdd8 Make jump threading substantially more powerful, in the following ways:
1. Make it fold blocks separated by an unconditional branch.  This enables
   jump threading to see a broader scope.
2. Make jump threading able to eliminate locally redundant loads when they
   feed the branch condition of a block.  This frequently occurs due to
   reg2mem running.
3. Make jump threading able to eliminate *partially redundant* loads when
   they feed the branch condition of a block.  This is common in code with
   lots of loads and stores like C++ code and 255.vortex.

This implements thread-loads.ll and rdar://6402033.

Per the fixme's, several pieces of this should be moved into Transforms/Utils.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60148 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 05:07:53 +00:00
Chris Lattner
ab8b794a78 Turn on my codegen prepare heuristic by default. It doesn't affect
performance in most cases on the Grawp tester, but does speed some 
things up (like shootout/hash by 15%).  This also doesn't impact 
compile time in a noticable way on the Grawp tester.

It also, of course, gets the testcase it was designed for right :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60120 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-26 22:16:44 +00:00
Chris Lattner
695d8ec33b teach the new heuristic how to handle inline asm.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60088 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-26 04:59:11 +00:00
Chris Lattner
896617b776 Improve ValueAlreadyLiveAtInst with a cheap and dirty, but effective
heuristic: the value is already live at the new memory operation if
it is used by some other instruction in the memop's block.  This is
cheap and simple to compute (moreso than full liveness).

This improves the new heuristic even more.  For example, it cuts two
out of three new instructions out of 255.vortex:DbmFileInGrpHdr, 
which is one of the functions that the heuristic regressed.  This
overall eliminates another 40 instructions from 403.gcc and visibly
reduces register pressure in 255.vortex (though this only actually
ends up saving the 2 instructions from the whole program).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60084 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-26 03:20:37 +00:00
Chris Lattner
84d1b40d44 Start rewroking a subpiece of the profitability heuristic to be
phrased in terms of liveness instead of as a horrible hack.  :)

In pratice, this doesn't change the generated code for either 
255.vortex or 403.gcc, but it could cause minor code changes in 
theory.  This is framework for coming changes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60082 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-26 03:02:41 +00:00
Chris Lattner
653b2581df add a comment, make save/restore logic more obvious.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60076 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-26 02:11:11 +00:00
Chris Lattner
5eecb7f164 This adds in some code (currently disabled unless you pass
-enable-smarter-addr-folding to llc) that gives CGP a better
cost model for when to sink computations into addressing modes.
The basic observation is that sinking increases register 
pressure when part of the addr computation has to be available
for other reasons, such as having a use that is a non-memory
operation.  In cases where it works, it can substantially reduce
register pressure.

This code is currently an overall win on 403.gcc and 255.vortex
(the two things I've been looking at), but there are several 
things I want to do before enabling it by default:

1. This isn't doing any caching of results, so it is much slower 
   than it could be.  It currently slows down release-asserts llc 
   by 1.7% on 176.gcc: 27.12s -> 27.60s.
2. This doesn't think about inline asm memory operands yet.
3. The cost model botches the case when the needed value is live
   across the computation for other reasons.

I'll continue poking at this, and eventually turn it on as llcbeta.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60074 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-26 02:00:14 +00:00
Evan Cheng
794a7dbce0 Revert r60042. IndVarSimplify should check if APFloat is PPCDoubleDouble first before trying to convert it to an integer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60072 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-26 01:11:57 +00:00
Chris Lattner
2efbbb38ba Teach CodeGenPrepare to look through Bitcast instructions when attempting to
optimize addressing modes.  This allows us to optimize things like isel-sink2.ll
into:

	movl	4(%esp), %eax
	cmpb	$0, 4(%eax)
	jne	LBB1_2	## F
LBB1_1:	## TB
	movl	$4, %eax
	ret
LBB1_2:	## F
	movzbl	7(%eax), %eax
	ret

instead of:

_test:
	movl	4(%esp), %eax
	cmpb	$0, 4(%eax)
	leal	4(%eax), %eax
	jne	LBB1_2	## F
LBB1_1:	## TB
	movl	$4, %eax
	ret
LBB1_2:	## F
	movzbl	3(%eax), %eax
	ret

This shrinks (e.g.) 403.gcc from 1133510 to 1128345 lines of .s.

Note that the 2008-10-16-SpillerBug.ll testcase is dubious at best, I doubt
it is really testing what it thinks it is.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60068 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-26 00:26:16 +00:00
Chris Lattner
3b48501adc Teach MatchScaledValue to handle Scales by 1 with MatchAddr (which
can recursively match things) and scales by 0 by ignoring them.
This triggers once in 403.gcc, saving 1 (!!!!) instruction in the 
whole huge app.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60013 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-25 07:25:26 +00:00
Chris Lattner
88a5c832ac significantly refactor all the addressing mode matching logic
into a new AddressingModeMatcher class.  This makes it easier
to reason about and reduces passing around of stuff, but has
no functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60012 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-25 07:09:13 +00:00
Chris Lattner
bb3204a440 refactor all the constantexpr/instruction handling code out into a
new FindMaximalLegalAddressingModeForOperation helper method.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60011 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-25 05:15:49 +00:00
Chris Lattner
7ad1c7342b another minor tweak
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60010 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-25 04:47:41 +00:00
Chris Lattner
088a1e84ea minor cleanups no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60009 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-25 04:42:10 +00:00
Chris Lattner
85fa13c02d rearrange and tidy some code, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59990 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-24 22:44:16 +00:00
Chris Lattner
4744d85c50 minor cleanups to debug code, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59989 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-24 22:40:05 +00:00
Chris Lattner
ae297f8da5 reenable the right part of the code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59985 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-24 21:26:21 +00:00