Commit Graph

162 Commits

Author SHA1 Message Date
Chris Lattner
89742c2c3f expand note.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90429 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-03 07:43:46 +00:00
Chris Lattner
053321731c add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90428 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-03 07:41:54 +00:00
Chris Lattner
d4137f40da update and consolidate the load pre notes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90050 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-29 02:19:52 +00:00
Chris Lattner
1d159838a3 add a deadargelim note.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90009 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 17:12:30 +00:00
Chris Lattner
6d94926a52 This testcase is actually only partially redundant, and requires
the FIXME I added yesterday to be implemented.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90008 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 16:53:57 +00:00
Chris Lattner
20ce7c0ded this (and probably several others) are now done.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89982 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 00:35:04 +00:00
Chris Lattner
cc3d0eb483 Teach memdep to phi translate bitcasts. This allows us to compile
the example in GCC PR16799 to:

LBB1_2:                                                     ## %bb1
	movl	%eax, %eax
	subq	%rax, %rdi
	movq	%rdi, (%rcx)
	movl	(%rdi), %eax
	testl	%eax, %eax
	je	LBB1_2

instead of:

LBB1_2:                                                     ## %bb1
	movl	(%rdi), %ecx
	subq	%rcx, %rdi
	movq	%rdi, (%rax)
	cmpl	$0, (%rdi)
	je	LBB1_2



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89978 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-26 23:41:07 +00:00
Chris Lattner
5d5261c819 Teach basicaa that x|c == x+c when the c bits of x are clear. This
allows us to compile the example in readme.txt into:

LBB1_1:                                                     ## %bb
	movl	4(%rdx,%rax), %ecx
	movl	%ecx, %esi
	imull	(%rdx,%rax), %esi
	imull	%esi, %ecx
	movl	%esi, 8(%rdx,%rax)
	imull	%ecx, %esi
	movl	%ecx, 12(%rdx,%rax)
	movl	%esi, 16(%rdx,%rax)
	imull	%ecx, %esi
	movl	%esi, 20(%rdx,%rax)
	addq	$16, %rax
	cmpq	$4000, %rax
	jne	LBB1_1

instead of:

LBB1_1: 
	movl	(%rdx,%rax), %ecx
	imull	4(%rdx,%rax), %ecx
	movl	%ecx, 8(%rdx,%rax)
	imull	4(%rdx,%rax), %ecx
	movl	%ecx, 12(%rdx,%rax)
	imull	8(%rdx,%rax), %ecx
	movl	%ecx, 16(%rdx,%rax)
	imull	12(%rdx,%rax), %ecx
	movl	%ecx, 20(%rdx,%rax)
	addq	$16, %rax
	cmpq	$4000, %rax
	jne	LBB1_1

GCC (4.2) doesn't seem to be able to eliminate the loads in this 
testcase either, it generates:

L2:
	movl	(%rdx), %eax
	imull	4(%rdx), %eax
	movl	%eax, 8(%rdx)
	imull	4(%rdx), %eax
	movl	%eax, 12(%rdx)
	imull	8(%rdx), %eax
	movl	%eax, 16(%rdx)
	imull	12(%rdx), %eax
	movl	%eax, 20(%rdx)
	addl	$4, %ecx
	addq	$16, %rdx
	cmpl	$1002, %ecx
	jne	L2




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89952 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-26 16:26:43 +00:00
Chris Lattner
f6ac4d9dad teach basicaa that A[i] != A[i+1].
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89951 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-26 16:18:10 +00:00
Chris Lattner
9c6a0dcf0e update some notes slightly
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89913 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-26 01:51:18 +00:00
Nick Lewycky
93f9f7a440 Add a complex missed optimization opportunity I came across while investigating
bug 5438.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@88855 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-15 17:51:23 +00:00
Chris Lattner
fc926c2395 another const prop failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86848 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-11 17:54:02 +00:00
Chris Lattner
6fdfc9c630 add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86847 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-11 17:51:27 +00:00
Chris Lattner
1742498b5a add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86756 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-10 23:47:45 +00:00
Chris Lattner
b6ad9153dd I did this a week or two ago
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86754 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-10 23:40:49 +00:00
Nick Lewycky
f80fcd00b3 Improve tail call elimination to handle the switch statement.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86403 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-07 21:10:15 +00:00
Chris Lattner
6c9fab7404 add a note from PR5313
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86146 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-05 18:19:19 +00:00
Bill Wendling
c872e9c07d Add new note.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85341 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-27 23:30:07 +00:00
Bill Wendling
5a56927345 Move and clarify note.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85334 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-27 22:48:31 +00:00
Chris Lattner
a1e1446056 this is done.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85041 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-25 06:17:51 +00:00
Chris Lattner
9ff9b34dd1 some stuff is done, we still have constantexpr simplification to do.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84943 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-23 07:00:55 +00:00
Chris Lattner
7d26443bb7 IPSCCP is missing stuff.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84725 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-21 01:10:37 +00:00
Chris Lattner
faa6adf67c add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82442 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-21 06:04:07 +00:00
Chris Lattner
93c6c77340 one case handled, expanded another testcase inline.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82427 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-21 02:53:57 +00:00
Chris Lattner
c1491f3c47 update an entry, delete an entry which has been fixed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82398 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-20 17:37:38 +00:00
Nick Lewycky
149cbc2a24 Peer through zext and sext to eliminate them when it is safe to do so.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82389 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-20 07:31:25 +00:00
Chris Lattner
c2b0d484dc add PR#
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81770 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-14 16:49:26 +00:00
Dan Gohman
9ca9daad21 Transform -X/C to X/-C, implementing a README.txt entry.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78812 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-12 16:37:02 +00:00
Eli Friedman
58bb61ae94 Remove a couple of already-implemented notes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76631 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-21 20:05:43 +00:00
Nick Lewycky
f16120475e Move PR4517 to README.txt.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75098 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-09 04:03:30 +00:00
Dan Gohman
81db61a2e6 Factor the code for collecting IV users out of LSR into an IVUsers class,
and generalize it so that it can be used by IndVarSimplify. Implement the
base IndVarSimplify transformation code using IVUsers. This removes
TestOrigIVForWrap and associated code, as ScalarEvolution now has enough
builtin overflow detection and folding logic to handle all the same cases,
and more. Run "opt -iv-users -analyze -disable-output" on your favorite
loop for an example of what IVUsers does.

This lets IndVarSimplify eliminate IV casts and compute trip counts in
more cases. Also, this happens to finally fix the remaining testcases
in PR1301.

Now that IndVarSimplify is being more aggressive, it occasionally runs
into the problem where ScalarEvolutionExpander's code for avoiding
duplicate expansions makes it difficult to ensure that all expanded
instructions dominate all the instructions that will use them. As a
temporary measure, IndVarSimplify now uses a FixUsesBeforeDefs function
to fix up instructions inserted by SCEVExpander. Fortunately, this code
is contained, and can be easily removed once a more comprehensive
solution is available.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71535 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-12 02:17:14 +00:00
Dan Gohman
1f3be1a1fe Fix two wording errors that Duncan spotted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71459 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-11 18:51:16 +00:00
Dan Gohman
0d9bb68d6d LLVM has unaligned loads and stores now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71449 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-11 18:06:05 +00:00
Dan Gohman
5c8274b5e3 Upgrade this example to new-style syntax.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71447 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-11 18:04:52 +00:00
Chris Lattner
32c5f17024 remove some done things: we have nocapture and SROA is smarter.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71443 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-11 17:41:40 +00:00
Chris Lattner
d919a8bc8a add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71442 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-11 17:36:33 +00:00
Eli Friedman
cea03cdb69 Remove a completed optimization. Add a potential optimization I ran
into.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71352 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-09 08:40:15 +00:00
Chris Lattner
352f3e5d37 add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67953 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-28 19:26:55 +00:00
Nick Lewycky
20babb112c Add a totally synthetic situation I came up with while looking at a bug in
related code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65437 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-25 06:52:48 +00:00
Torok Edwin
474479fce7 add note about sin
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65137 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-20 18:42:06 +00:00
Torok Edwin
e46a686dc2 add note about possible GEP improvement with fields of size 0.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62925 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-24 19:30:25 +00:00
Chris Lattner
256baa4b1f add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62760 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-22 07:16:03 +00:00
Dan Gohman
8289b05c4c Add a README entry noticed while investigating PR3216.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62558 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-20 01:07:33 +00:00
Chris Lattner
9fee08fce7 add some more crazy strlen and memcpy stuff I noticed in spec.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61918 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-08 07:34:55 +00:00
Chris Lattner
ffb08f569b add some notes about strlen craziness in eon.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61917 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-08 06:52:57 +00:00
Chris Lattner
d23b799d7d add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61513 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-31 00:54:13 +00:00
Chris Lattner
9cf8ef63c6 add some notes for simplifylibcalls optimizations
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61385 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-23 20:52:52 +00:00
Chris Lattner
582048d5b8 add some more notes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61033 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 08:32:28 +00:00
Chris Lattner
8f416f3afd Add a testcase for GCC PR 23455, which lpre handles now. Add some
comments about why we're not getting other cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61032 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 07:49:24 +00:00
Chris Lattner
ef423ebdd1 gvn now hoists this load out of the hot non-call path.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61028 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 06:34:48 +00:00