Commit Graph

130 Commits

Author SHA1 Message Date
Chris Lattner
bc9a28dd54 constant fold loads from memcpy's from global constants. This is important
because clang lowers nontrivial automatic struct/array inits to memcpy from
a global array.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90698 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-06 05:29:56 +00:00
Chris Lattner
cb9cbc4949 add support for forwarding mem intrinsic values to non-local loads.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90697 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-06 04:54:31 +00:00
Chris Lattner
faf815b938 Handle forwarding local memsets to loads. For example, we optimize this:
short x(short *A) {
  memset(A, 1, sizeof(*A)*100);
  return A[42];
}

to 'return 257' instead of doing the load.  



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90695 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-06 01:57:02 +00:00
Chris Lattner
f616ee2895 merge two tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90691 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-06 01:47:24 +00:00
Chris Lattner
e4968a4b9d Small and carefully crafted testcase showing a miscompilation by GVN
that I'm working on.  This is manifesting as a miscompile of 255.vortex
on some targets.  No check lines yet because it fails.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90520 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-04 02:12:12 +00:00
Owen Anderson
c9f2027adb Fix this crasher, and add a FIXME for a missed optimization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90408 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-03 03:43:29 +00:00
Chris Lattner
fd82af0f95 add a failing testcase.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90380 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-03 01:46:18 +00:00
Owen Anderson
9ff5a23186 Cleanup/remove some parts of the lifetime region handling code in memdep and GVN,
per Chris' comments.  Adjust testcases to match.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90304 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-02 07:35:19 +00:00
Chris Lattner
49f5389aae minimize this a bit more.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90216 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-01 07:30:01 +00:00
Chris Lattner
156cf873e5 merge 2009-11-29-ReverseMap.ll into crash.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90212 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-01 06:22:10 +00:00
Nick Lewycky
526bc31cee Add a testcase for the current llvm-gcc build failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90112 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-30 07:02:18 +00:00
Chris Lattner
ff0a883fe9 add PR#
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90049 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-29 01:28:58 +00:00
Chris Lattner
78c6d4fa9c Add a testcase for:
void test(int N, double* G) {
  long j;
  for (j = 1; j < N - 1; j++)
      G[j] = G[j] + G[j+1] + G[j-1];
}

which we now compile to one load in the loop:

LBB1_2:                                                     ## %bb
	movsd	16(%rsi,%rax,8), %xmm2
	incq	%rdx
	addsd	%xmm2, %xmm1
	addsd	%xmm1, %xmm0
	movapd	%xmm2, %xmm1
	movsd	%xmm0, 8(%rsi,%rax,8)
	incq	%rax
	cmpq	%rcx, %rax
	jne	LBB1_2

instead of:

LBB1_2:                                                     ## %bb
	movsd	8(%rsi,%rax,8), %xmm0
	addsd	16(%rsi,%rax,8), %xmm0
	addsd	(%rsi,%rax,8), %xmm0
	movsd	%xmm0, 8(%rsi,%rax,8)
	incq	%rax
	cmpq	%rcx, %rax
	jne	LBB1_2



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90048 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-29 01:15:43 +00:00
Chris Lattner
9fed3c2835 add a testcase for
void test9(int N, double* G) {
  long j;
  for (j = 1; j < N - 1; j++)
      G[j+1] = G[j] + G[j+1];
}



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90047 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-29 01:04:40 +00:00
Chris Lattner
0c264b16b0 reenable load address insertion in load pre. This allows us to
handle cases like this:
void test(int N, double* G) {
  long j;
  for (j = 1; j < N - 1; j++)
      G[j+1] = G[j] + G[j+1];
}

where G[1] isn't live into the loop.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90041 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-28 16:08:18 +00:00
Chris Lattner
971fd57f7d disable value insertion for now, I need to figure out how
to inform GVN about the newly inserted values.  This fixes 
PR5631.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90022 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 22:50:07 +00:00
Chris Lattner
253be4ddb2 I accidentally implemented this :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90014 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 19:56:00 +00:00
Chris Lattner
11c6bab704 add support for recursive phi translation and phi
translation of add with immediate.  This allows us
to optimize this function:

void test(int N, double* G) {
  long j;
  G[1] = 1;
    for (j = 1; j < N - 1; j++)
        G[j+1] = G[j] + G[j+1];
}

to only do one load every iteration of the loop.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90013 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 19:11:31 +00:00
Chris Lattner
9a5c22cc5e add two simple test cases we now optimize (to one load in the loop each) and one we don't (corresponding to the fixme I added yesterday).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90012 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 18:08:30 +00:00
Chris Lattner
616613d7a4 teach GVN's load PRE to insert computations of the address in predecessors
where it is not available.  It's unclear how to get this inserted 
computation into GVN's scalar availability sets, Owen, help? :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89997 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 08:25:10 +00:00
Chris Lattner
d280d85791 add some tests for memdep phi translation + PRE.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89996 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 06:42:42 +00:00
Chris Lattner
852dfbdf02 this test is failing, and is expected to.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89995 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 06:36:28 +00:00
Chris Lattner
8dca876ab7 filecheckize
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89994 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 06:33:09 +00:00
Chris Lattner
9b15d60c7a rename test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89993 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 06:31:55 +00:00
Chris Lattner
62deff066c Fix phi translation in load PRE to agree with the phi
translation done by memdep, and reenable gep translation 
again.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89992 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 06:31:14 +00:00
Chris Lattner
b99be5beac redisable this, my bootstrap worked because it wasn't an optimized build, whoops.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89991 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 05:53:01 +00:00
Chris Lattner
cca130bb66 try again.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89990 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 05:19:56 +00:00
Chris Lattner
518c988ae9 this is causing buildbot failures, disable for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89985 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 01:52:22 +00:00
Chris Lattner
e19e4baf3b teach phi translation of GEPs to simplify geps like 'gep x, 0'.
This allows us to compile the example from PR5313 into:

LBB1_2:                                                     ## %bb
	incl	%ecx
	movb	%al, (%rsi)
	movslq	%ecx, %rax
	movb	(%rdi,%rax), %al
	testb	%al, %al
	jne	LBB1_2

instead of:

LBB1_2:                                                     ## %bb
	movslq	%eax, %rcx
	incl	%eax
	movb	(%rdi,%rcx), %cl
	movb	%cl, (%rsi)
	movslq	%eax, %rcx
	cmpb	$0, (%rdi,%rcx)
	jne	LBB1_2



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89981 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 00:34:38 +00:00
Chris Lattner
304076268a teach memdep to do trivial PHI translation of GEPs. More to
come.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89979 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 00:07:37 +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
38028653a9 convert to filecheck
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89977 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-26 23:32:59 +00:00
Benjamin Kramer
5da15364b9 Try to work around grep's "Binary file (standard input) matches" complaints seen
on ppc buildbot.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89452 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-20 09:53:25 +00:00
Dan Gohman
f94b5edc45 Extend CaptureTracking to indicate when a value is never stored, even
if it is not ultimately captured. Teach BasicAliasAnalysis that a 
local object address which does not escape and is never stored does
not alias with a value resulting from a load.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89398 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-19 21:57:48 +00:00
Dan Gohman
f75ef668a7 Default-addressspace null pointers don't alias anything. This allows
GVN to be more aggressive. Patch by Hans Wennborg! (with a comment added by me)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86582 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-09 19:29:11 +00:00
Owen Anderson
b62f792e78 Treat lifetime begin/end markers as allocations/frees respectively for the
purposes for GVN/DSE.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85383 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-28 07:05:35 +00:00
Owen Anderson
a85a66423d Be more careful about invariance reasoning on "store" queries. Stores still need
to depend on Ref and ModRef calls within the invariant region.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85380 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-28 06:30:52 +00:00
Owen Anderson
4bc737c5ef Add trivial support for the invariance intrinsics to memdep. This logic is
purely local for now.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85378 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-28 06:18:42 +00:00
Duncan Sands
0f2bd97434 Check that GVN performs this transform even if the calls
themselves are not marked readonly, but only the called
functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84253 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-16 12:18:23 +00:00
Victor Hernandez
5c78736f85 Memory dependence analysis was incorrectly stopping to scan for stores to a pointer at bitcast uses of a malloc call.
It should continue scanning until the malloc call, and this patch fixes that.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83931 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-13 01:42:53 +00:00
Chris Lattner
a09fbf0af0 switch GVN to use SSAUpdater. Besides removing a lot of complexity
from GVN, this also speeds it up, inserts fewer PHI nodes (see the
testcase) and allows it to remove more loads (due to fewer PHI nodes
standing in the way).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83746 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-10 23:50:30 +00:00
Chris Lattner
8b2bc3d574 fix PR5016, a crash I introduced in GVN handing first class
arrays and structs, which cannot be bitcast to integers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82460 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-21 17:24:04 +00:00
Chris Lattner
4fbd14e80e enable non-local analysis and PRE of large store -> little load.
This doesn't kick in too much because of phi translation issues,
but this can be resolved in the future.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82447 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-21 06:48:08 +00:00
Chris Lattner
f716330c90 add pr#
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82440 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-21 05:57:47 +00:00
Chris Lattner
eed919b1ba Improve GVN to be able to forward substitute a small load
from a piece of a large store when both are in the same block.

This allows clang to compile the testcase in PR4216 to this code:

_test_bitfield:
	movl	4(%esp), %eax
	movl	%eax, %ecx
	andl	$-65536, %ecx
	orl	$32962, %eax
	andl	$40186, %eax
	orl	%ecx, %eax
	ret

This is not ideal, but is a whole lot better than the code produced
by llvm-gcc:

_test_bitfield:
	movw	$-32574, %ax
	orw	4(%esp), %ax
	andw	$-25350, %ax
	movw	%ax, 4(%esp)
	movw	7(%esp), %cx
	shlw	$8, %cx
	movzbl	6(%esp), %edx
	orw	%cx, %dx
	movzwl	%dx, %ecx
	shll	$16, %ecx
	movzwl	%ax, %eax
	orl	%ecx, %eax
	ret

and dramatically better than that produced by gcc 4.2:

_test_bitfield:
	pushl	%ebx
	call	L3
"L00000000001$pb":
L3:
	popl	%ebx
	movl	8(%esp), %eax
	leal	0(,%eax,4), %edx
	sarb	$7, %dl
	movl	%eax, %ecx
	andl	$7168, %ecx
	andl	$-7201, %ebx
	movzbl	%dl, %edx
	andl	$1, %edx
	sall	$5, %edx
	orl	%ecx, %ebx
	orl	%edx, %ebx
	andl	$24, %eax
	andl	$-58336, %ebx
	orl	%eax, %ebx
	orl	$32962, %ebx
	movl	%ebx, %eax
	popl	%ebx
	ret



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82439 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-21 05:57:11 +00:00
Chris Lattner
8111576521 fix a FileCheck bug where:
; CHECK: foo
; CHECK-NOT: foo
; CHECK: bar

would always fail.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82424 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-21 02:30:42 +00:00
Daniel Dunbar
3d4138bd58 Work around a FileCheck bug, for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82416 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-20 23:30:31 +00:00
Chris Lattner
66364346e0 Revert r82404, it is causing a bootstrap miscompile. This is very very
scary, as it indicates a lurking bug. yay.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82411 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-20 22:44:26 +00:00
Chris Lattner
6a089c3257 this was not supposed to be committed
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82409 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-20 22:36:11 +00:00
Chris Lattner
f15380ba8a implement and document support for CHECK-NOT
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82408 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-20 22:35:26 +00:00