Commit Graph

3389 Commits

Author SHA1 Message Date
Benjamin Kramer
91e37ef278 InstCombine: Add a bunch of combines of the form x | (y ^ z).
We usually catch this kind of optimization through InstSimplify's distributive
magic, but or doesn't distribute over xor in general.

"A | ~(A | B) -> A | ~B" hits 24 times on gcc.c.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126081 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-20 13:23:43 +00:00
Nick Lewycky
1a4021a2be Teach RecursivelyDeleteDeadPHINodes to handle multiple self-references. Patch
by Andrew Clinton!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126077 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-20 08:38:20 +00:00
Eli Friedman
1347623aaf PR9218: SimplifyDemandedVectorElts can return a non-null value that is not
the instruction passed in.  Make sure to account for this correctly, instead
of looping infinitely.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126058 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-19 22:42:40 +00:00
Chris Lattner
80e8b506b8 rewrite the memset_pattern pattern generation stuff to accept any 2/4/8/16-byte
constant, including globals.  This makes us generate much more "pretty" pattern
globals as well because it doesn't break it down to an array of bytes all the
time.

This enables us to handle stores of relocatable globals.  This kicks in about
48 times in 254.gap, giving us stuff like this:

@.memset_pattern40 = internal constant [2 x %struct.TypHeader* (%struct.TypHeader*, %struct.TypHeader*)*] [%struct.TypHeader* (%struct.TypHeader*, %struct
.TypHeader*)* @IsFalse, %struct.TypHeader* (%struct.TypHeader*, %struct.TypHeader*)* @IsFalse], align 16

...
  call void @memset_pattern16(i8* %scevgep5859, i8* bitcast ([2 x %struct.TypHeader* (%struct.TypHeader*, %struct.TypHeader*)*]* @.memset_pattern40 to i8*
), i64 %tmp75) nounwind



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126044 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-19 19:56:44 +00:00
Chris Lattner
41bfbb0a87 Stores of null pointers should turn into memset, we weren't recognizing
them as splat values.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126041 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-19 19:35:49 +00:00
Chris Lattner
3a393728a6 Implement rdar://9009151, transforming strided loop stores of
unsplatable values into memset_pattern16 when it is available
(recent darwins).  This transforms lots of strided loop stores
of ints for example, like 5 in vpr:

  Formed memset:   call void @memset_pattern16(i8* %4, i8* getelementptr inbounds ([16 x i8]* @.memset_pattern9, i32 0, i32 0), i64 %tmp25)
    from store to: {%3,+,4}<%11> at:   store i32 3, i32* %scevgep, align 4, !tbaa !4




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126040 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-19 19:31:39 +00:00
Duncan Sands
39a7de72c8 Add some transforms of the kind X-Y>X -> 0>Y which are valid when there is no
overflow.  These subsume some existing equality transforms, so zap those.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125843 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-18 16:25:37 +00:00
Chris Lattner
67982da351 add a testcase for r125827
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125831 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-18 05:05:01 +00:00
Chris Lattner
78f7a25f98 prevent jump threading from merging blocks when their address is
taken (and used!).  This prevents merging the blocks (invalidating
the block addresses) in a case like this:

#define _THIS_IP_  ({ __label__ __here; __here: (unsigned long)&&__here; })

void foo() {
  printf("%p\n", _THIS_IP_);
  printf("%p\n", _THIS_IP_);
  printf("%p\n", _THIS_IP_);
}

which fixes PR4151.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125829 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-18 04:43:06 +00:00
Chris Lattner
c8cb8ef9c2 have instcombine preserve nsw/nuw/exact when sinking
common operations through a phi. 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125790 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-17 23:01:49 +00:00
Chris Lattner
4bd8217af3 fix instcombine merging GEPs through a PHI to only make the
result inbounds if all of the inputs are inbounds.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125785 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-17 22:21:26 +00:00
Nadav Rotem
093399cbf3 Enhance constant folding of bitcast operations on vectors of floats.
Add getAllOnesValue of FP numbers to Constants and APFloat.
Add more tests.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125776 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-17 21:22:27 +00:00
Duncan Sands
a77243300b Transform "A + B >= A + C" into "B >= C" if the adds do not wrap. Likewise for some
variations (some of these were already present so I unified the code).  Spotted by my
auto-simplifier as occurring a lot.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125734 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-17 07:46:37 +00:00
Chris Lattner
41429e3f1e preserve NUW/NSW when transforming add x,x
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125711 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-17 02:23:02 +00:00
Chris Lattner
3e468e1efa filecheckize
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125710 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-17 02:21:03 +00:00
Chris Lattner
de1d8a544c fix PR9215, preventing -reassociate from clearing nsw/nuw when
it swaps the LHS/RHS of a single binop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125700 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-17 01:29:24 +00:00
Nick Lewycky
8a670edf1b Teach PatternMatch that splat vectors could be floating point as well as
integer. Fixes PR9228!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125613 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-15 23:13:23 +00:00
Nadav Rotem
d9e087bbc3 Fix 9216 - Endless loop in InstCombine pass.
The pattern "A&(A^B) -> A & ~B" recreated itself because ~B is
actually a xor -1.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125557 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-15 07:13:48 +00:00
Devang Patel
3fc178ffda Do not hoist @llvm.dbg.value. Here, @llvm.dbg.value is "referring" a value that is modified inside loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125529 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-14 23:03:23 +00:00
Duncan Sands
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
Nadav Rotem
d239e5af64 Fix test
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125460 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-13 16:13:16 +00:00
Nadav Rotem
bc53ca1b53 Fix a regression from r125393;
It caused a crash in MultiSource/Benchmarks/Bullet.
Opt hit an assertion with "opt -std-compile-opts" because
Constant::getAllOnesValue doesn't know how to handle floats.

This patch added a test to reproduce the problem and a check that the
destination vector is of integer type.

Thank you Benjamin!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125459 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-13 15:45:34 +00:00
Chris Lattner
b289b40744 add PR#
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125455 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-13 08:27:31 +00:00
Chris Lattner
bb75d337c4 implement instcombine folding for things like (x >> c) < 42.
We were previously simplifying divisions, but not right shifts!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125454 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-13 08:07:21 +00:00
Daniel Dunbar
d02be24cad SimplifyLibCalls: Add missing legalize check on various printf to puts and
putchar transforms, their return values are not compatible.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125442 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-12 18:19:57 +00:00
Daniel Dunbar
43186a4ea9 tests: FileCheckize
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125441 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-12 18:19:53 +00:00
Benjamin Kramer
b6c8cb4422 Also fold (A+B) == A -> B == 0 when the add is commuted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125411 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-11 21:46:48 +00:00
Nadav Rotem
d2f27ead2d Fix 9173.
Add more folding patterns to constant expressions of vector selects and vector
bitcasts.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125393 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-11 19:37:55 +00:00
Cameron Zwarich
a2f9d4e053 Add a test for the LSR issue exposed by r125254.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125325 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-11 00:49:27 +00:00
Nick Lewycky
3b739d278c Tolerate degenerate phi nodes that can occur in the middle of optimization
passes. Fixes PR9112. Patch by Jakub Staszak!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125319 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-10 23:54:10 +00:00
Cameron Zwarich
4a60b932a2 Rename 'loopsimplify' to 'loop-simplify'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125317 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-10 23:38:10 +00:00
Chris Lattner
6cdf2ea98e implement the first part of PR8882: when lowering an inbounds
gep to explicit addressing, we know that none of the intermediate
computation overflows.

This could use review: it seems that the shifts certainly wouldn't
overflow, but could the intermediate adds overflow if there is a 
negative index?

Previously the testcase would instcombine to:

define i1 @test(i64 %i) {
  %p1.idx.mask = and i64 %i, 4611686018427387903
  %cmp = icmp eq i64 %p1.idx.mask, 1000
  ret i1 %cmp
}

now we get:

define i1 @test(i64 %i) {
  %cmp = icmp eq i64 %i, 1000
  ret i1 %cmp
}



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125271 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-10 07:11:16 +00:00
Chris Lattner
7a6aa1a391 Enhance a bunch of transformations in instcombine to start generating
exact/nsw/nuw shifts and have instcombine infer them when it can prove
that the relevant properties are true for a given shift without them.

Also, a variety of refactoring to use the new patternmatch logic thrown
in for good luck.  I believe that this takes care of a bunch of related
code quality issues attached to PR8862.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125267 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-10 05:36:31 +00:00
Chris Lattner
b20c0b5092 Enhance the "compare with shift" and "compare with div"
optimizations to be much more aggressive in the face of
exact/nsw/nuw div and shifts.  For example, these (which
are the same except the first is 'exact' sdiv:

define i1 @sdiv_icmp4_exact(i64 %X) nounwind {
  %A = sdiv exact i64 %X, -5   ; X/-5 == 0 --> x == 0
  %B = icmp eq i64 %A, 0
  ret i1 %B
}

define i1 @sdiv_icmp4(i64 %X) nounwind {
  %A = sdiv i64 %X, -5   ; X/-5 == 0 --> x == 0
  %B = icmp eq i64 %A, 0
  ret i1 %B
}

compile down to:

define i1 @sdiv_icmp4_exact(i64 %X) nounwind {
  %1 = icmp eq i64 %X, 0
  ret i1 %1
}

define i1 @sdiv_icmp4(i64 %X) nounwind {
  %X.off = add i64 %X, 4
  %1 = icmp ult i64 %X.off, 9
  ret i1 %1
}

This happens when you do something like:
  (ptr1-ptr2) == 42

where the pointers are pointers to non-unit types.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125266 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-10 05:23:05 +00:00
Chris Lattner
44cc997d42 more cleanups, notably bitcast isn't used for "signed to unsigned type
conversions". :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125265 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-10 05:17:27 +00:00
Chris Lattner
81a0dc9115 Teach instsimplify some tricks about exact/nuw/nsw shifts.
improve interfaces to instsimplify to take this info.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125196 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-09 17:15:04 +00:00
Chris Lattner
6bfd77e315 merge two tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125195 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-09 17:06:41 +00:00
Nick Lewycky
3ba974a1c5 When removing a function from the function set and adding it to deferred, we
could end up removing a different function than we intended because it was
functionally equivalent, then end up with a comparison of a function against
itself in the next round of comparisons (the one in the function set and the
one on the deferred list). To fix this, I introduce a choice in the form of
comparison for ComparableFunctions, either normal or "pointer only" used to
find exact Function*'s in lookups.

Also add some debugging statements.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125180 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-09 06:32:02 +00:00
Benjamin Kramer
33828bcb24 SimplifyCFG: Track the number of used icmps when turning a icmp chain into a switch. If we used only one icmp, don't turn it into a switch.
Also prevent the switch-to-icmp transform from creating identity adds, noticed by Marius Wachtler.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125056 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-07 22:37:28 +00:00
Chris Lattner
c6ee9181a5 teach instsimplify to transform (X / Y) * Y to X
when the div is an exact udiv.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124994 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-06 22:05:31 +00:00
Chris Lattner
c35a44d3d7 rename test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124993 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-06 21:59:10 +00:00
Chris Lattner
35bda8914c enhance vmcore to know that udiv's can be exact, and add a trivial
instcombine xform to exercise this.

Nothing forms exact udivs yet though.  This is progress on PR8862



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124992 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-06 21:44:57 +00:00
Anders Carlsson
6475d9434f When loading from a constant, fold inttoptr if the integer type and the resulting pointer type both have the same size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124987 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-06 20:11:56 +00:00
Benjamin Kramer
042b27f40e SimplifyCFG: Also transform switches that represent a range comparison but are not sorted into sub+icmp.
This transforms another 1000 switches in gcc.c.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124826 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-03 22:51:41 +00:00
Duncan Sands
50ca4d37f7 Improve threading of comparisons over select instructions (spotted by my
auto-simplifier).  This has a big impact on Ada code, but not much else.
Unfortunately the impact is mostly negative!  This is due to PR9004 (aka
SCCP failing to resolve conditional branch conditions in the destination
blocks of the branch), in which simple correlated expressions are not
resolved but complicated ones are, so simplifying has a bad effect!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124788 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-03 09:37:39 +00:00
Duncan Sands
4b720718fb Reenable the transform "(X*Y)/Y->X" when the multiplication is known not to
overflow (nsw flag), which was disabled because it breaks 254.gap.  I have
informed the GAP authors of the mistake in their code, and arranged for the
testsuite to use -fwrapv when compiling this benchmark.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124746 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-02 20:52:00 +00:00
Benjamin Kramer
56442dfdcf SimplifyCFG: Turn switches into sub+icmp+branch if possible.
This makes the job of the later optzn passes easier, allowing the vast amount of
icmp transforms to chew on it.

We transform 840 switches in gcc.c, leading to a 16k byte shrink of the resulting
binary on i386-linux.

The testcase from README.txt now compiles into
  decl  %edi
  cmpl  $3, %edi
  sbbl  %eax, %eax
  andl  $1, %eax
  ret

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124724 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-02 15:56:22 +00:00
Dan Gohman
46985a1440 Fix reassociate to clear optional flags, such as nsw.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124712 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-02 02:02:34 +00:00
Duncan Sands
7681c6da60 Have m_One also match constant vectors for which every element is 1.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124655 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-01 08:39:12 +00:00
Anders Carlsson
77bc49e5e2 Recognize and simplify
(A+B) == A  ->  B == 0
A == (A+B)  ->  B == 0



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124567 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-30 22:01:13 +00:00