Commit Graph

239 Commits

Author SHA1 Message Date
Chris Lattner
e405c64f6b move DecomposeGEPExpression out into ValueTracking.cpp
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89956 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-26 17:12:50 +00:00
Chris Lattner
fa3966881f teach GetLinearExpression to be a bit more aggressive.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89955 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-26 17:00:01 +00:00
Chris Lattner
5369250b73 resolve a fixme. I haven't figured out how to write a testcase
to exercise this though.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89954 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-26 16:52:32 +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
d84eb911a9 Change the other half of aliasGEP (which handles GEP differencing) to use DecomposeGEPExpression. This dramatically simplifies and shrinks the code by eliminating the horrible CheckGEPInstructions method, fixes a miscompilation (@test3) and makes the code more aggressive. In particular, we now handle the @test4 case, which is reduced from the SmallPtrSet constructor. Missing this caused us to emit a variable length memset instead of a fixed size one.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89922 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-26 02:17:34 +00:00
Chris Lattner
23e2a5b2ff Generalize DecomposeGEPExpression to exactly handle what Value::getUnderlyingObject does (when TD is around). This allows us to avoid calling DecomposeGEPExpression unless the ultimate alias check we care about passes, speedup up BasicAA a bit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89920 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-26 02:14:59 +00:00
Chris Lattner
4e91ee7a2a Implement a new DecomposeGEPExpression method, which decomposes a GEP into a list of scaled offsets. Use this to eliminate some previous ad-hoc code which was subtly broken (it assumed all Constant*'s were non-zero, but strange constant express could be zero).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89915 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-26 02:13:03 +00:00
Chris Lattner
539c9b99c2 Use GEPOperator more pervasively to simplify code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89914 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-26 02:11:08 +00:00
Chris Lattner
b27db37ed0 fix comment, thanks all :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89666 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-23 17:07:35 +00:00
Chris Lattner
403ac2ece3 use the new isNoAlias method to simplify some code, only do an escaping check if
we have a non-constant pointer.  Constant pointers can't be local.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89665 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-23 16:46:41 +00:00
Chris Lattner
5d56b2d47d whitespace cleanup, tidying
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89664 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-23 16:45:27 +00:00
Chris Lattner
b34b82e9d1 speed up BasicAA a bit by implementing a long-standing TODO.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89663 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-23 16:44:43 +00:00
Chris Lattner
6c7276f17e add fixme for dubious code. Duncan, what do you think?
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89602 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-22 16:16:48 +00:00
Chris Lattner
4723303c97 remove a silly condition that doesn't make a lot of sense anymore.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89601 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-22 16:15:59 +00:00
Chris Lattner
92e803c2a4 reduce indentation, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89600 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-22 16:05:05 +00:00
Chris Lattner
66e08cf79a Remove the AliasAnalysis::getMustAliases method, which is dead.
The hasNoModRefInfoForCalls isn't worth it as a filter because 
basicaa provides m/r info and everything chains to it, so remove
it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89599 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-22 16:01:44 +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
Nick Lewycky
20162ac566 Teach BasicAA that a constant expression can't alias memory provably not
allocated until runtime (such as an alloca). Patch by Hans Wennborg!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@88760 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-14 06:15:14 +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
Chris Lattner
7b550ccfc5 remove a bunch of extraneous LLVMContext arguments
from various APIs, addressing PR5325.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86231 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-06 04:27:31 +00:00
Victor Hernandez
f006b183e2 Rename MallocFreeHelper as MemoryBuiltins
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85286 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-27 20:05:49 +00:00
Victor Hernandez
f2becca90b Rename MallocHelper as MallocFreeHelper, since it now also identifies calls to free()
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85181 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-26 23:58:56 +00:00
Dan Gohman
6665b0ea68 Teach BasicAA how to analyze Select instructions, and make it more
aggressive on PHI instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85158 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-26 21:55:43 +00:00
Nick Lewycky
f5a86f45e7 Remove includes of Support/Compiler.h that are no longer needed after the
VISIBILITY_HIDDEN removal.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85043 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-25 06:57:41 +00:00
Nick Lewycky
6726b6d75a Remove VISIBILITY_HIDDEN from class/struct found inside anonymous namespaces.
Chris claims we should never have visibility_hidden inside any .cpp file but
that's still not true even after this commit.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85042 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-25 06:33:48 +00:00
Victor Hernandez
7b929dad59 Remove AllocationInst. Since MallocInst went away, AllocaInst is the only subclass of AllocationInst, so it no longer is necessary.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84969 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-23 21:09:37 +00:00
Chris Lattner
391d23b6c2 inline isGEP away.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84373 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-17 23:48:54 +00:00
Evan Cheng
a846a8a1dc When checking aliases between phi sources and V2, we know the sources are not themselves phi nodes. However, V2 may be. Call aliasCheck with V2 first to potentially eliminate a std::swap call.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84226 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-16 00:33:09 +00:00
Nick Lewycky
20312d0bb8 Add missing break statements! Thanks to Duncan Sands for pointing this out!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84191 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-15 18:48:58 +00:00
Nick Lewycky
6e9e010752 Teach basicaa about memcpy/memmove/memset. The length argument can be used to
improve alias results if constant, and the source pointer can't be modified.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84175 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-15 07:11:24 +00:00
Nick Lewycky
2d3820c29c Teach BasicAA to use the size parameter of the memory use marker intrinsics.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84174 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-15 06:12:11 +00:00
Nick Lewycky
22c031296c Take advantage of TargetData when available; we know that the atomic intrinsics
only dereference the element they point to directly with no pointer arithmetic.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84159 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-15 00:36:35 +00:00
Evan Cheng
f0429fd1ca Clear VisitedPHIs after use.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84080 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-14 06:46:26 +00:00
Evan Cheng
681a33e26d Another BasicAA fix. If a value does not alias a GEP's base pointer, then it
cannot alias the GEP. GEP pointer alias rule states this clearly:
A pointer value formed from a getelementptr instruction is associated with the
addresses associated with the first operand of the getelementptr.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84079 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-14 06:41:49 +00:00
Evan Cheng
d83c2ca336 More code clean up based on patch feedback.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84074 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-14 05:22:03 +00:00
Evan Cheng
3dbe43b1b5 Change VisitedPHIs into an instance variable that's freed by each alias() call.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84072 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-14 05:05:02 +00:00
Evan Cheng
50a5914e12 Teach basic AA about PHI nodes. If all operands of a phi NoAlias another value than it's safe to declare the PHI NoAlias the value. Ditto for MustAlias.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84038 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-13 22:02:20 +00:00
Evan Cheng
094f04b429 Refactor some code. No functionality changes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84000 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-13 18:42:04 +00:00
Nick Lewycky
5c9be67cff Teach BasicAA a little something about the atomic intrinsics: they can only
modify through the pointer they're given.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83959 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-13 07:48:38 +00:00
Victor Hernandez
46e8312fb7 Enhance analysis passes so that they apply the same analysis to malloc calls as to MallocInst.
Reviewed by Eli Friedman.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82281 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-18 21:34:51 +00:00
Dan Gohman
aae87cde50 Use stripPointerCasts instead of doing the same manually.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80267 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-27 18:02:03 +00:00
Owen Anderson
1d0be15f89 Push LLVMContexts through the IntegerType APIs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78948 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-13 21:58:54 +00:00
Owen Anderson
a7235ea724 Move a few more APIs back to 2.5 forms. The only remaining ones left to change back are
metadata related, which I'm waiting on to avoid conflicting with Devang.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77721 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-31 20:28:14 +00:00
Owen Anderson
baf3c40440 Move ConstantExpr to 2.5 API.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77494 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-29 18:55:55 +00:00
Dan Gohman
fc2a3ed0c9 Make AliasAnalysis and related classes use
getAnalysisIfAvailable<TargetData>().


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77028 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-25 00:48:42 +00:00
Owen Anderson
eed707b1e6 Revert the ConstantInt constructors back to their 2.5 forms where possible, thanks to contexts-on-types. More to come.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77011 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-24 23:12:02 +00:00
Owen Anderson
e922c02019 Get rid of the Pass+Context magic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76702 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-22 00:24:57 +00:00
Dan Gohman
f241174421 Revert the addition of hasNoPointerOverflow to GEPOperator.
Getelementptrs that are defined to wrap are virtually useless to
optimization, and getelementptrs that are undefined on any kind
of overflow are too restrictive -- it's difficult to ensure that
all intermediate addresses are within bounds. I'm going to take
a different approach.

Remove a few optimizations that depended on this flag.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76437 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-20 17:43:30 +00:00
Dan Gohman
3a7a68c108 Make BasicAliasAnalysis and Value::getUnderlyingObject use
GEPOperator's hasNoPointer0verflow(), and make a few places in instcombine
that create GEPs that may overflow clear the NoOverflow value. Among
other things, this partially addresses PR2831.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76252 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-17 22:25:10 +00:00