Commit Graph

180 Commits

Author SHA1 Message Date
1e4e1c768b Teach instsimplify to be more aggressive when analyzing comparisons of pointers
by using llvm::isIdentifiedObject. Also teach it to handle GEPs that have
the same base pointer and constant operands. Fixes PR11238!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151449 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-25 19:07:42 +00:00
009e2650d6 fix PR12075, a regression in a recent transform I added. In unreachable code, gep chains can be infinite. Just like "stripPointerCasts", use a set to keep track of visited instructions so we don't recurse infinitely.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151383 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-24 19:01:58 +00:00
b053fc1c92 fold comparisons of gep'd alloca points with null to false,
implementing PR12013.  We now compile the testcase to:

__Z4testv:                              ## @_Z4testv
## BB#0:                                ## %_ZN4llvm15SmallVectorImplIiE9push_backERKi.exit
	pushq	%rbx
	subq	$64, %rsp
	leaq	32(%rsp), %rbx
	movq	%rbx, (%rsp)
	leaq	64(%rsp), %rax
	movq	%rax, 16(%rsp)
	movl	$1, 32(%rsp)
	leaq	36(%rsp), %rax
	movq	%rax, 8(%rsp)
	leaq	(%rsp), %rdi
	callq	__Z1gRN4llvm11SmallVectorIiLj8EEE
	movq	(%rsp), %rdi
	cmpq	%rbx, %rdi
	je	LBB0_2
## BB#1:
	callq	_free
LBB0_2:                                 ## %_ZN4llvm11SmallVectorIiLj8EED1Ev.exit
	addq	$64, %rsp
	popq	%rbx
	ret

instead of:

__Z4testv:                              ## @_Z4testv
## BB#0:
	pushq	%rbx
	subq	$64, %rsp
	xorl	%eax, %eax
	leaq	(%rsp), %rbx
	addq	$32, %rbx
	movq	%rbx, (%rsp)
	movq	%rbx, 8(%rsp)
	leaq	64(%rsp), %rcx
	movq	%rcx, 16(%rsp)
	je	LBB0_2
## BB#1:
	movl	$1, 32(%rsp)
	movq	%rbx, %rax
LBB0_2:                                 ## %_ZN4llvm15SmallVectorImplIiE9push_backERKi.exit
	addq	$4, %rax
	movq	%rax, 8(%rsp)
	leaq	(%rsp), %rdi
	callq	__Z1gRN4llvm11SmallVectorIiLj8EEE
	movq	(%rsp), %rdi
	cmpq	%rbx, %rdi
	je	LBB0_4
## BB#3:
	callq	_free
LBB0_4:                                 ## %_ZN4llvm11SmallVectorIiLj8EED1Ev.exit
	addq	$64, %rsp
	popq	%rbx
	ret

This doesn't shrink clang noticably though.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150944 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-20 00:42:49 +00:00
2c3acb0e27 Fix a rather nasty regression from r150690: LHS != RHS does not imply LHS->stripPointerCasts() != RHS->stripPointerCasts().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150863 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-18 03:29:25 +00:00
ea79b8e03c Revert "InstSimplify: Strip pointer casts early."
Turns out this isn't safe, because the code below depends on LHS and RHS having
the same type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150695 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-16 15:19:59 +00:00
475ebf5a74 InstSimplify: Strip pointer casts early.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150694 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-16 15:03:04 +00:00
fd8779a94b InstSimplify: Ignore pointer casts when constant folding compares between pointers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150690 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-16 13:49:39 +00:00
aa97bb54f0 Fix PR11948: the result type of an icmp may be a vector of boolean -
don't assume it is a boolean.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150247 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-10 14:31:24 +00:00
858143816d Convert assert(0) to llvm_unreachable
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149967 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-07 05:05:23 +00:00
55c6d57734 PatternMatch: Introduce a matcher for instructions with the "exact" bit. Use it to simplify a few matchers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147403 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-01 17:55:30 +00:00
1608769abe Add support for vectors of pointers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145801 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-05 06:29:09 +00:00
618c1dbd29 Propagate TargetLibraryInfo throughout ConstantFolding.cpp and
InstructionSimplify.cpp.  Other fixups as needed.
Part of rdar://10500969

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145559 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-01 03:08:23 +00:00
66d004ef70 Make use of "getScalarType()". No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145556 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-01 02:39:36 +00:00
7781ae5be5 Fix code to match comment. Fixes PR11340, a regression from r143209.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144121 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-08 21:08:02 +00:00
71d0503157 Teach instsimplify to simplify calls to undef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143719 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-04 18:32:42 +00:00
6dc9e2bf74 Reapply commit 143214 with a fix: m_ICmp doesn't match conditions
with the given predicate, it matches any condition and returns the
predicate - d'oh!  Original commit message:
The expression icmp eq (select (icmp eq x, 0), 1, x), 0 folds to false.
Spotted by my super-optimizer in 186.crafty and 450.soplex.  We really
need a proper infrastructure for handling generalizations of this kind
of thing (which occur a lot), however this case is so simple that I decided
to go ahead and implement it directly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143318 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-30 19:56:36 +00:00
09c3253d30 Revert r143214; it's breaking a bunch of stuff.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143265 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-29 00:56:07 +00:00
012f8547f7 The expression icmp eq (select (icmp eq x, 0), 1, x), 0 folds to false.
Spotted by my super-optimizer in 186.crafty and 450.soplex.  We really
need a proper infrastructure for handling generalizations of this kind
of thing (which occur a lot), however this case is so simple that I decided
to go ahead and implement it directly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143214 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-28 19:01:20 +00:00
c65c747bc4 Fold icmp ugt (udiv X, Y), X to false. Spotted by my super-optimizer
in 186.crafty.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143209 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-28 18:17:44 +00:00
32a43cc0fc Reapply commit 143028 with a fix: the problem was casting a ConstantExpr Mul
using BinaryOperator (which only works for instructions) when it should have
been a cast to OverflowingBinaryOperator (which also works for constants).
While there, correct a few other dubious looking uses of BinaryOperator.
Thanks to Chad Rosier for the testcase.  Original commit message:
My super-optimizer noticed that we weren't folding this expression to
true: (x *nsw x) sgt 0, where x = (y | 1).  This occurs in 464.h264ref.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143125 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-27 19:16:21 +00:00
dd3149d579 The maximum power of 2 dividing a power of 2 is itself. This occurs
in 403.gcc and was spotted by my super-optimizer.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143054 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-26 20:55:21 +00:00
ae707bd559 InstSimplify: Don't try to replace an extractvalue/insertvalue pair with the original value if types don't match.
Fixes clang selfhost.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139120 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-05 18:16:19 +00:00
dabc280672 Add some simple insertvalue simplifications, for the purpose of cleaning
up do-nothing exception handling code produced by dragonegg.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139113 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-05 06:52:48 +00:00
f23d4adbfa Revert r137781; I agree with Duncan's comment that the situation in question is clearly impossible given the current structure of the code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137853 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-17 19:31:49 +00:00
207634263c Extend the undef ^ undef idiom once more. No testcase: I can't figure out how to actually trigger the codepath in question at the moment, but it might get exposed in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137781 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-16 22:38:34 +00:00
c9d904ee2c Fix what seems an obvious typo. Patch by Ivan Krasin. Problem
reported at http://habrahabr.ru/blogs/compilers/125626/.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136865 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-04 10:02:21 +00:00
f56138d4ae Add helper function for getting true/false constants in a uniform
way for i1 and vector of i1 types.  Use these to make some code
more self-documenting.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136079 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-26 15:03:53 +00:00
a9203109f4 Convert GetElementPtrInst to use ArrayRef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135904 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-25 09:48:08 +00:00
dab3d29605 Convert ConstantExpr::getGetElementPtr and
ConstantExpr::getInBoundsGetElementPtr to use ArrayRef.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135673 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-21 14:31:17 +00:00
b9b54ebfed Convert SimplifyGEPInst to use ArrayRef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135482 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-19 15:07:52 +00:00
1d2f569c34 Use ArrayRef in ConstantFoldInstOperands and ConstantFoldCall.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135477 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-19 13:32:40 +00:00
db125cfaf5 land David Blaikie's patch to de-constify Type, with a few tweaks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135375 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-18 04:54:35 +00:00
68c0dbc14f Improve constant folding of undef for cmp and select operators.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134223 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-01 01:03:43 +00:00
e864b5b840 The comparision "max(x,y)==x" is equivalent to "x>=y". Since the max is
often expressed as "x >= y ? x : y", there is a good chance we can extract
the existing "x >= y" from it and use that as a replacement for "max(x,y)==x".


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131049 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-07 16:56:49 +00:00
b6e7cd655c PR9838: Fix transform introduced in r127064 to not trigger when only one side of the icmp is an exact shift.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130954 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-05 21:59:18 +00:00
8140ad32ce Add variations on: max(x,y) >= min(x,z) folds to true. This isn't that common,
but according to my super-optimizer there are only two missed simplifications
of -instsimplify kind when compiling bzip2, and this is one of them.  It amuses
me to have bzip2 be perfectly optimized as far as instsimplify goes!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130840 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-04 16:05:05 +00:00
ad20681cde Implement some basic simplifications involving min/max, for example
max(a,b) >= a -> true.  According to my super-optimizer, these are
by far the most common simplifications (of the -instsimplify kind)
that occur in the testsuite and aren't caught by -std-compile-opts.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130780 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-03 19:53:10 +00:00
448a6d3cc2 Fix PR9579: when simplifying a compare to "true" or "false", and it was
a vector compare, generate a vector result rather than i1 (and crashing).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130706 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-02 18:51:41 +00:00
f24ed77d24 Move some rem transforms out of instcombine and into instsimplify.
This automagically provides a transform noticed by my super-optimizer
as occurring quite often: "rem x, (select cond, x, 1)" -> 0.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130694 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-02 16:27:02 +00:00
562b84b3ae Don't include Operator.h from InstrTypes.h.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129271 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-11 09:35:34 +00:00
a0e2f38b25 Fix two cases I forgot to update when doing a mental "getSwappedPredicate".
Thanks Duncan Sands!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127323 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-09 08:20:06 +00:00
84dd4fa2e3 Add another micro-optimization. Apologies for the lack of refactoring, but I
gave up when I realized I couldn't come up with a good name for what the
refactored function would be, to describe what it does.

This is PR9343 test12, which is test3 with arguments reordered. Whoops!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127318 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-09 06:26:03 +00:00
58bfcdbcf6 Thread comparisons over udiv/sdiv/ashr/lshr exact and lshr nuw/nsw whenever
possible. This goes into instcombine and instsimplify because instsimplify
doesn't need to check hasOneUse since it returns (almost exclusively) constants.

This fixes PR9343 #4 #5 and #8!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127064 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-05 05:19:11 +00:00
e2ee753bc4 Revert broken srem logic from r126991.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127021 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-04 19:26:08 +00:00
786792784e Fold "icmp pred (srem X, Y), Y" like we do for urem. Handle signed comparisons
in the urem case, though not the other way around. This is enough to get #3 from
PR9343!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126991 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-04 10:06:52 +00:00
3a73e343d0 Teach instruction simplify to use constant ranges to solve problems of the form
"icmp pred %X, CI" and a number of examples where "%X = binop %Y, CI2".

Some of these cases (div and rem) used to make it through opt -O2, but the
others are probably now making code elsewhere redundant (probably instcombine).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126988 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-04 07:00:57 +00:00
88cd0aadb2 Optimize "icmp pred (urem X, Y), Y" --> true/false depending on pred. There's
more work to do here, "icmp ult (urem X, 10), 11" doesn't optimize away yet.
Fixes example 3 from PR9343!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126741 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-01 08:15:50 +00:00
38f7f66fcc Move "A | ~(A & ?) -> -1" from InstCombine to InstructionSimplify.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126082 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-20 15:20:01 +00:00
5380d28070 Remove pointless blank line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125463 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-13 18:11:05 +00:00
52fb846578 Teach instsimplify that X+Y>=X+Z is the same as Y>=Z if neither side overflows,
plus some variations of this.  According to my auto-simplifier this occurs a lot
but usually in combination with max/min idioms.  Because max/min aren't handled
yet this unfortunately doesn't have much effect in the testsuite.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125462 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-13 17:15:40 +00:00