Commit Graph

2856 Commits

Author SHA1 Message Date
Eli Friedman
be7cfa6033 Simplify/generalize the xor+add->sign-extend instcombine.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94943 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-31 04:29:12 +00:00
Eli Friedman
694488f477 Add a small transform: transform -(X<<Y) to (-X<<Y) when the shift has a single
use and X is free to negate.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94941 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-31 02:30:23 +00:00
Evan Cheng
56a5886b20 Do not mark no-return calls tail calls. It'll screw up special calls like longjmp and it doesn't make much sense for performance reason. If my logic is faulty, please let me know.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94937 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-31 00:59:31 +00:00
Bob Wilson
49db68fba0 Check alignment of loads when deciding whether it is safe to execute them
unconditionally.  Besides checking the offset, also check that the underlying
object is aligned as much as the load itself.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94875 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-30 04:42:39 +00:00
Bob Wilson
8ad1f0e284 Remove ARM-specific calling convention from this test. Target data is
needed for this test, but otherwise, there's nothing ARM-specific about
it and no need to specify the calling convention.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94862 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-30 00:40:23 +00:00
Eric Christopher
36664bfc7a Revert my last couple of patches. They appear to have broken bison.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94841 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 21:16:24 +00:00
Bob Wilson
3eb4f7e2dd Improve isSafeToLoadUnconditionally to recognize that GEPs with constant
indices are safe if the result is known to be within the bounds of the
underlying object.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94829 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 19:19:08 +00:00
Eric Christopher
407e47c21e Make strcpy_chk lower to strcpy if we have a safe size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94783 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 01:37:11 +00:00
Eric Christopher
949124ce0f Add constant support to object size handling and remove default
lowering. We'll either figure it out, or not and be lowered by
SelectionDAGBuild.

Add test.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94775 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 01:09:57 +00:00
Duncan Sands
2c47368a7d Fix PR6165. The bug was that LHSKnownZero was being and'd with DemandedMask
when it should have been and'd with LowBits.  Fix that and while there beef
up the logic in the case of a negative LHS.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94745 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-28 17:22:42 +00:00
Bob Wilson
e98585eb36 Avoid creating redundant PHIs in SSAUpdater::GetValueInMiddleOfBlock.
This was already being done in SSAUpdater::GetValueAtEndOfBlock so I've
just changed SSAUpdater to check for existing PHIs in both places.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94690 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-27 22:01:02 +00:00
Victor Hernandez
b7ae53f035 When converting dbg.declare to dbg.value, attach promoted store's debug metadata to dbg.value
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94634 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-27 00:44:36 +00:00
Dan Gohman
8a977e2edd -disable-output is no longer needed with -analyze.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94574 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-26 19:25:59 +00:00
Victor Hernandez
b9768b0731 In mem2reg, for all alloca/stores that get promoted where the alloca has an associated llvm.dbg.declare instrinsic, insert an llvm.dbg.var intrinsic before each store.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94493 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-26 02:42:15 +00:00
Victor Hernandez
aee6a656e8 Revert r94260 until findDbgDeclare() is made more efficient
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94432 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-25 17:52:13 +00:00
Chris Lattner
abb992d6a3 change the canonical form of "cond ? -1 : 0" to be
"sext cond" instead of a select.  This simplifies some instcombine
code, matches the policy for zext (cond ? 1 : 0 -> zext), and allows
us to generate better code for a testcase on ppc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94339 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-24 00:09:49 +00:00
Nick Lewycky
44540740ae Speculatively revert r94322 to see if it fixes darwin selfhost buildbot.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94331 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 20:32:12 +00:00
Chris Lattner
d668839cb9 third bug from PR6119: the xor dupe extension allows
for arbitrary terminators in predecessors, don't assume
it is a conditional or uncond branch.  The testcase shows
an example where they can happen with switches.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94323 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 19:21:31 +00:00
Nick Lewycky
dbeecede80 Teach DAE that even though it can't modify the function signature of an
externally visible function, it can still find all callers of it and replace
the parameters to a dead argument with undef.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94322 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 19:19:34 +00:00
Chris Lattner
2dd7657a5b add an early out to ProcessBranchOnXOR to speed it up,
handle the case when we can infer an input to the xor
from all inputs that agree, instead of going into an
infinite loop.  Another part of PR6199


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94321 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 19:16:25 +00:00
Chris Lattner
8231fd1e6c fix a crash in jump threading, PR6119
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94319 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 18:56:07 +00:00
Chris Lattner
818ff34bc0 implement a simple instcombine xform that has been in the
readme forever.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94318 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 18:49:30 +00:00
Mon P Wang
e4a0a151a5 InstCombine should not fold sext/zext of a vector and a bitcast to a scalar to a sext/zext
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94280 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 04:35:57 +00:00
Victor Hernandez
b6aebc2f46 In mem2reg, for all alloca/stores that get promoted where the alloca has an associated llvm.dbg.declare instrinsic, insert an llvm.dbg.var intrinsic before each store
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94260 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 00:17:34 +00:00
Dan Gohman
7979b72feb Revert LoopStrengthReduce.cpp to pre-r94061 for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94123 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-22 00:46:49 +00:00
Nick Lewycky
401f3258f6 Fix a crasher trying to fold each element in a comparison between two vectors
if one of the vectors didn't have elements (such as undef). Fixes PR 6096.

Fix an issue in the constant folder where fcmp (<2 x %ty>, <2 x %ty>) would
have <2 x i1> type if constant folding was successful and i1 type if it wasn't.
This exposed a related issue in the bitcode reader.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94069 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 07:03:21 +00:00
Dan Gohman
a10756ee65 Re-implement the main strength-reduction portion of LoopStrengthReduction.
This new version is much more aggressive about doing "full" reduction in
cases where it reduces register pressure, and also more aggressive about
rewriting induction variables to count down (or up) to zero when doing so
reduces register pressure.

It currently uses fairly simplistic algorithms for finding reuse
opportunities, but it introduces a new framework allows it to combine
multiple strategies at once to form hybrid solutions, instead of doing
all full-reduction or all base+index.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94061 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 02:09:26 +00:00
Dan Gohman
8e1aa8edec Add nounwinds.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93919 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-19 21:51:51 +00:00
Chris Lattner
c0404b3715 optimize ~(~X >>s Y) --> (X >>s Y), patch by Edmund Grimley
Evans!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93884 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-19 18:16:19 +00:00
Bob Wilson
a756b1d914 Fix a crash in scalarrepl for memcpy/memmove where the source and destination
are the same.  I had already fixed a similar problem where the source and
destination were different bitcasts derived from the same alloca, but the
previous fix still did not handle the case where both operands are exactly
the same value.  Radar 7552893.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93848 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-19 04:32:48 +00:00
Chris Lattner
cd5adbbc0c my instcombine transformations to make extension elimination more
aggressive changed the canonical form from sext(trunc(x)) to ashr(lshr(x)),
make sure to transform a couple more things into that canonical form,
and catch a case where we missed turning zext/shl/ashr into a single sext.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93787 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-18 22:19:16 +00:00
Chris Lattner
1dafbe1738 filecheckize this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93776 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-18 22:00:46 +00:00
Chris Lattner
f08872048f filecheckize
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93775 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-18 21:58:32 +00:00
Chris Lattner
569a7b9237 remove a redundant test, filecheckize another.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93774 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-18 21:55:43 +00:00
Bill Wendling
4eb66b8d0e Reduce fsub-fadd.ll and merge it into fsub-fsub.ll. Rename fsub-fsub.ll to
fsub.ll and FileCheckify it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93669 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-17 00:21:21 +00:00
Bill Wendling
22f3b9faac When the visitSub method was split into visitSub and visitFSub, this xform was
added to the FSub version. However, the original version of this xform guarded
against doing this for floating point (!Op0->getType()->isFPOrFPVector()).

This is causing LLVM to perform incorrect xforms for code like:

void func(double *rhi, double *rlo, double xh, double xl, double yh, double yl){
  double mh, ml;
  double c = 134217729.0;
  double up, u1, u2, vp, v1, v2;
        
  up = xh*c;
  u1 = (xh - up) + up;
  u2 = xh - u1;
        
  vp = yh*c;
  v1 = (yh - vp) + vp;
  v2 = yh - v1;
        
  mh = xh*yh;
  ml = (((u1*v1 - mh) + (u1*v2)) + (u2*v1)) + (u2*v2);
  ml += xh*yl + xl*yh;
        
  *rhi = mh + ml;
  *rlo = (mh - (*rhi)) + ml;
}

The last line was optimized away, but rl is intended to be the difference
between the infinitely precise result of mh + ml and after it has been rounded
to double precision.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93369 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-13 23:23:17 +00:00
Chris Lattner
972a46c96a 1) Use the new SimplifyInstructionsInBlock routine instead of the copy
in JT.

2) When cloning blocks for PHI or xor conditions, use
instsimplify to simplify the code as we go.  This allows us to 
squish common cases early in JT which opens up opportunities for
subsequent iterations, and allows it to completely simplify the
testcase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93253 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-12 20:41:47 +00:00
Dan Gohman
ad4f7a6882 Make several tests less fragile.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93230 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-12 04:52:47 +00:00
Chris Lattner
2249a0b1bd Teach jump threading to duplicate small blocks when the branch
condition is a xor with a phi node.  This eliminates nonsense
like this from 176.gcc in several places:

 LBB166_84:
        testl   %eax, %eax
-       setne   %al
-       xorb    %cl, %al
-       notb    %al
-       testb   $1, %al
-       je      LBB166_85
+       je      LBB166_69
+       jmp     LBB166_85

This is rdar://7391699



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93221 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-12 02:07:17 +00:00
Chris Lattner
8c2143fce9 disable this testcase, PR5997
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93206 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11 23:18:33 +00:00
Chris Lattner
8e76764de8 add one more bitfield optimization, allowing clang to generate
good code on PR4216:

_test_bitfield:                                             ## @test_bitfield
	orl	$32962, %edi
	movl	$4294941946, %eax
	andq	%rdi, %rax
	ret

instead of:

_test_bitfield:
        movl    $4294941696, %ecx
        movl    %edi, %eax
        orl     $194, %edi
        orl     $32768, %eax
        andq    $250, %rdi
        andq    %rax, %rcx
        movq    %rdi, %rax
        orq     %rcx, %rax
        ret

Evan is looking into the remaining andq+imm -> andl optimization.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93147 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11 06:55:24 +00:00
Chris Lattner
7acc4b1281 Extend CanEvaluateZExtd to handle and/or/xor more aggressively in the
BitsToClear case.  This allows it to promote expressions which have an
and/or/xor after the lshr, promoting cases like test2 (from PR4216) 
and test3 (random extample extracted from a spec benchmark).

clang now compiles the code in PR4216 into:

_test_bitfield:                                             ## @test_bitfield
	movl	%edi, %eax
	orl	$194, %eax
	movl	$4294902010, %ecx
	andq	%rax, %rcx
	orl	$32768, %edi
	andq	$39936, %rdi
	movq	%rdi, %rax
	orq	%rcx, %rax
	ret

instead of:

_test_bitfield:                                             ## @test_bitfield
	movl	%edi, %eax
	orl	$194, %eax
	movl	$4294902010, %ecx
	andq	%rax, %rcx
	shrl	$8, %edi
	orl	$128, %edi
	shlq	$8, %rdi
	andq	$39936, %rdi
	movq	%rdi, %rax
	orq	%rcx, %rax
	ret

which is still not great, but is progress.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93145 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11 04:05:13 +00:00
Chris Lattner
789162a309 Remove the dead TD argument to CanEvaluateZExtd, and add a
new BitsToClear result which allows us to start promoting
expressions that end with a lshr-by-constant.  This is
conservatively correct and better than what we had before
(see testcases) but still needs to be extended further.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93144 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11 03:32:00 +00:00
Chris Lattner
11ea812424 teach sext optimization to handle truncs from types that are not
the dest of the sext.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93128 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 20:30:41 +00:00
Chris Lattner
9ee947c224 teach zext optimization how to deal with truncs that don't come from
the zext dest type.  This allows us to handle test52/53 in cast.ll,
and allows llvm-gcc to generate much better code for PR4216 in -m64
mode:

_test_bitfield:                                             ## @test_bitfield
	orl	$32962, %edi
	movl	%edi, %eax
	andl	$-25350, %eax
	ret

This also fixes a bug handling vector extends, ensuring that the
mask produced is a vector constant, not an integer constant.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93127 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 20:25:54 +00:00
Chris Lattner
dde5ee5d37 now that the cost model has changed, we can always consider
elimination of a sign extend to be a win, which simplifies 
the client of CanEvaluateSExtd, and allows us to eliminate
more casts (examples taken from real code).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93109 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 07:40:50 +00:00
Chris Lattner
f4fb91181c change the preferred canonical form for a sign extension to be
lshr+ashr instead of trunc+sext.  We want to avoid type 
conversions whenever possible, it is easier to codegen expressions
without truncates and extensions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93107 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 07:08:30 +00:00
Chris Lattner
5324d80283 two changes:
1) don't try to optimize a sext or zext that is only used by a trunc, let
   the trunc get optimized first.  This avoids some pointless effort in
   some common cases since instcombine scans down a block in the first pass.
2) Change the cost model for zext elimination to consider an 'and' cheaper
   than a zext.  This allows us to do it more aggressively, and for the next
   patch to simplify the code quite a bit.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93097 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 02:39:31 +00:00
Chris Lattner
d26c9e183e enhance CanEvaluateZExtd to handle shift left and sext, allowing
more expressions to be promoted and casts eliminated.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93096 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 02:22:12 +00:00
Dan Gohman
3073329c53 Use WriteAsOperand instead of getName() to print loop header names,
so that unnamed blocks are handled.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93059 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-09 18:17:45 +00:00
Chris Lattner
c2d1b6949c only factor from expressions whose uses are empty and whose
base is the right expression type.  This fixes PR5981.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93045 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-09 06:01:36 +00:00
Chris Lattner
a85732fa3b teach instcombine to delete sign extending shift pairs (sra(shl X, C), C) when
the input is already sign extended.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93019 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-08 19:04:21 +00:00
Chris Lattner
b31189f262 fix PR5978 by peeling the loop so that we avoid shifting the
result int by 8 for the first byte.  While normally harmless,
if the result is smaller than a byte, this shift is invalid.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93018 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-08 19:02:23 +00:00
Chris Lattner
8d10f9d4a8 teach ComputeNumSignBits to look through PHI nodes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92964 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-07 23:44:37 +00:00
Chris Lattner
e3874deb61 filecheckize
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92963 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-07 23:42:23 +00:00
Chris Lattner
075f692939 Enhance instcombine to reason more strongly about promoting computation
that feeds into a zext, similar to the patch I did yesterday for sext.
There is a lot of room for extension beyond this patch.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92962 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-07 23:41:00 +00:00
Chris Lattner
a0e9a2475c fix a globalopt crash on 'bullet' (handling evaluation of a store
to an element of a vector in a static ctor) which occurs with an 
unrelated patch I'm testing.  Annoyingly, EvaluateStoreInto basically 
does exactly the same stuff as InsertElement constant folding, but it
now handles vectors, and you can't insertelement into a vector.  It
would be 'really nice' if GEP into a vector were not legal.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92889 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-07 01:16:21 +00:00
Duncan Sands
e10920d678 Fix a README item: have functionattrs look through selects and
phi nodes when deciding which pointers point to local memory.
I actually checked long ago how useful this is, and it isn't
very: it hardly ever fires in the testsuite, but since Chris
wants it here it is!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92836 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-06 15:37:47 +00:00
Duncan Sands
7c422ac216 Partially address a README by having functionattrs consider calls to
memcpy, memset and other intrinsics that only access their arguments
to be readnone if the intrinsic's arguments all point to local memory.
This improves the testcase in the README to readonly, but it could in
theory be made readnone, however this would involve more sophisticated
analysis that looks through the memcpy.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92829 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-06 08:45:52 +00:00
Chris Lattner
e0e4cc7fd5 Teach instcombine's sext elimination logic to be more aggressive.
Previously, instcombine would only promote an expression tree to
the larger type if doing so eliminated two casts.  This is because
a need to manually do the sign extend after the promoted expression
tree with two shifts.  Now, we keep track of whether the result of
the computation is going to be properly sign extended already.  If
so, we can unconditionally promote the expression, which allows us
to zap more sext's.

This implements rdar://6598839 (aka gcc pr38751)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92815 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-06 01:56:21 +00:00
Dan Gohman
d7d1a29003 Move this test from test/Transforms/IndVarSimplify to
test/CodeGen/X86, as doesn't use -indvars, and it does use
llc -march=x86-64.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92799 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 22:52:54 +00:00
Chris Lattner
7a34d6c450 more rearrangement and cleanup, fix my test failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92792 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 22:21:18 +00:00
Chris Lattner
c0f79af143 remove two trunc xforms that are subsumed by EvaluateInDifferentType.
The only difference is that EvaluateInDifferentType checks to ensure
they are profitable before doing them :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92788 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 22:01:41 +00:00
Chris Lattner
c04d3d37e4 merge some tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92786 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 21:54:09 +00:00
Chris Lattner
50ca0204c5 merge cast2 into cast.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92784 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 21:48:13 +00:00
Chris Lattner
6ae68a28b9 remove useless test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92782 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 21:46:22 +00:00
Chris Lattner
8e66905ce8 another example.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92781 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 21:43:08 +00:00
Chris Lattner
022bd99d10 remove a useless negative test, add a rdar # to an xfail that I'm working on.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92777 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 21:37:44 +00:00
Chris Lattner
a8f3ebbf5c clean up tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92776 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 21:32:59 +00:00
Chris Lattner
464dc81803 just remove this xform which is subsumed by others.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92775 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 21:16:30 +00:00
Chris Lattner
033574074d optimize comparisons against cttz/ctlz/ctpop, patch by Alastair Lynn!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92745 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 18:09:56 +00:00
Dan Gohman
aceba31b7a Delete useless trailing semicolons.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92740 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 17:55:26 +00:00
Chris Lattner
16507fe9fd optimize cttz and ctlz when we can prove something about the
leading/trailing bits.  Patch by Alastair Lynn!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92706 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 07:23:56 +00:00
Chris Lattner
5f94af0f72 fix an infinite loop in reassociate building emacs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92679 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 04:55:35 +00:00
Devang Patel
44a29e066a Remove dead debug info intrinsics.
Intrinsic::dbg_stoppoint
 Intrinsic::dbg_region_start 
 Intrinsic::dbg_region_end 
 Intrinsic::dbg_func_start
AutoUpgrade simply ignores these intrinsics now.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92557 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 01:10:40 +00:00
Chris Lattner
d7f5a58890 Truncate GEP indexes larger than the pointer size down to pointer size
when doing this transform if the GEP is not inbounds.  No testcase because
it is very difficult to trigger this: instcombine already canonicalizes
GEP indices to pointer size, so it relies specific permutations of the
instcombine worklist.

Thanks to Duncan for pointing this possible problem out.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92495 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-04 18:57:15 +00:00
Chris Lattner
e4412c1f0b implement an instcombine xform needed by clang's codegen
on the example in PR4216.  This doesn't trigger in the testsuite,
so I'd really appreciate someone scrutinizing the logic for
correctness.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92458 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-04 06:03:59 +00:00
Chris Lattner
56ba7a74b9 generalize the previous transformation to handle indexing into
arrays of structs and other arrays, so long as all the subsequent
indexes are constants.  This triggers frequently for stuff like:

@divisions = internal constant [29 x [2 x i32]] [[2 x i32] zeroinitializer, [2 x i32] [i32 0, i32 1], [2 x i32] [i32 0, i32 2], [2 x i32] [i32 0, i32 1], [2 x i32] zeroinitializer, [2 x i32] [i32 0, i32 1], [2 x i32] [i32 0, i32 1], [2 x i32] [i32 0, i32 2], [2 x i32] [i32 0, i32 2], [2 x i32] zeroinitializer, [2 x i32] zeroinitializer, [2 x i32] zeroinitializer, [2 x i32] [i32 0, i32 2], [2 x i32] [i32 0, i32 1], [2 x i32] zeroinitializer, [2 x i32] [i32 1, i32 0], [2 x i32] [i32 1, i32 1], [2 x i32] [i32 1, i32 1], [2 x i32] [i32 1, i32 2], [2 x i32] [i32 1, i32 1], [2 x i32] [i32 1, i32 0], [2 x i32] [i32 1, i32 2], [2 x i32] [i32 1, i32 2], [2 x i32] [i32 1, i32 0], [2 x i32] [i32 1, i32 0], [2 x i32] [i32 1, i32 0], [2 x i32] [i32 1, i32 1], [2 x i32] [i32 1, i32 2], [2 x i32] [i32 1, i32 2]], align 32 ; <[29 x [2 x i32]]*> [#uses=50]

	  %623 = getelementptr inbounds [29 x [2 x i32]]* @divisions, i64 0, i64 %619, i64 0 ; <i32*> [#uses=1]
	   %684 = icmp eq i32 %683, 999 

also for the "my_defs" table in 'gs', etc.




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92444 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-03 03:03:27 +00:00
Chris Lattner
df3d63b896 teach instcombine to optimize idioms like A[i]&42 == 0. This
occurs in 403.gcc in mode_mask_array, in safe-ctype.c (which
is copied in multiple apps) in _sch_istable, etc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92427 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 22:08:28 +00:00
Chris Lattner
b4f82b4b4f Teach the table lookup optimization to generate range compares
when a consequtive sequence of elements all satisfies the 
predicate.  Like the double compare case, this generates better
code than the magic constant case and generalizes to more than
32/64 element array lookups.

Here are some examples where it triggers.  From 403.gcc, most
accesses to the rtx_class array are handled, e.g.:

@rtx_class = constant [153 x i8] c"xxxxxmmmmmmmmxxxxxxxxxxxxmxxxxxxiiixxxxxxxxxxxxxxxxxxxooxooooooxxoooooox3x2c21c2222ccc122222ccccaaaaaa<<<<<<<<<<<<<<<<<<111111111111bbooxxxxxxxxxxcc2211x", align 32 ; <[153 x i8]*> [#uses=547]
   %142 = icmp eq i8 %141, 105
@rtx_class = constant [153 x i8] c"xxxxxmmmmmmmmxxxxxxxxxxxxmxxxxxxiiixxxxxxxxxxxxxxxxxxxooxooooooxxoooooox3x2c21c2222ccc122222ccccaaaaaa<<<<<<<<<<<<<<<<<<111111111111bbooxxxxxxxxxxcc2211x", align 32 ; <[153 x i8]*> [#uses=543]
	   %165 = icmp eq i8 %164, 60      

Also, most of the 59-element arrays (mode_class/rid_to_yy, etc) 
optimized before are actually range compares.  This lets 32-bit
machines optimize them.

400.perlbmk has stuff like this:

400.perlbmk: PL_regkind, even for 32-bit:
@PL_regkind = constant [62 x i8] c"\00\00\02\02\02\06\06\06\06\09\09\0B\0B\0D\0E\0E\0E\11\12\12\14\14\16\16\18\18\1A\1A\1C\1C\1E\1F !!!$$&'((((,-.///88886789:;8$", align 32 ; <[62 x i8]*> [#uses=4]
	   %811 = icmp ne i8 %810, 33 

@PL_utf8skip = constant [256 x i8] c"\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\01\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\02\03\03\03\03\03\03\03\03\03\03\03\03\03\03\03\03\04\04\04\04\04\04\04\04\05\05\05\05\06\06\07\0D", align 32 ; <[256 x i8]*> [#uses=94]
	   %12 = icmp ult i8 %10, 2
           
etc.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92426 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 21:50:18 +00:00
Nick Lewycky
f994bf00b5 Fix logic error in previous commit. The != case needs to become an or, not an
and.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92419 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 16:14:56 +00:00
Nick Lewycky
546d63176e Optimize pointer comparison into the typesafe form, now that the backends will
handle them efficiently. This is the opposite direction of the transformation
we used to have here.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92418 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 15:25:44 +00:00
Chris Lattner
bef37376be Generalize the previous xform to handle cases where exactly
two elements match or don't match with two comparisons.  For
example, the testcase compiles into:

define i1 @test5(i32 %X) {
  %1 = icmp eq i32 %X, 2                          ; <i1> [#uses=1]
  %2 = icmp eq i32 %X, 7                          ; <i1> [#uses=1]
  %R = or i1 %1, %2                               ; <i1> [#uses=1]
  ret i1 %R
}

This generalizes the previous xforms when the array is larger than
64 elements (and this case matches) and generates better code for
cases where it overlaps with the magic bitshift case.

This generalizes more cases than you might expect.  For example,
400.perlbmk has:

@PL_utf8skip = constant [256 x i8] c"\01\01\01\...
%15 = icmp ult i8 %7, 7

403.gcc has:
@rid_to_yy = internal constant [114 x i16] [i16 259, i16 260, ...
%18 = icmp eq i16 %16, 295 

and xalancbmk has a bunch of examples, such as 
_ZN11xercesc_2_5L15gCombiningCharsE and _ZN11xercesc_2_5L10gBaseCharsE.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92417 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 09:35:17 +00:00
Chris Lattner
10d514ee58 enhance the compare/load/index optimization to work on *any* load
from a global with 32/64 elements or less (depending on whether
i64 is native on the target), generating a bitshift idiom to 
determine the result.  For example, on test4 we produce:

define i1 @test4(i32 %X) {
  %1 = lshr i32 933, %X                           ; <i32> [#uses=1]
  %2 = and i32 %1, 1                              ; <i32> [#uses=1]
  %R = icmp ne i32 %2, 0                          ; <i1> [#uses=1]
  ret i1 %R
}

This triggers in a number of interesting cases, for example, here's an
fp case:
@A.3255 = internal constant [4 x double] [double 4.100000e+00, double -3.900000e+00, double -1.000000e+00, double 1.000000e+00], align 32 ; <[4 x double]*> [#uses=7]
...
	   %7 = fcmp olt double %3, 0.000000e+00

In this case we make the slen2_tab global dead, which is nice:
@slen2_tab = internal constant [16 x i32] [i32 0, i32 1, i32 2, i32 3, i32 0, i32 1, i32 2, i32 3, i32 1, i32 2, i32 3, i32 1, i32 2, i32 3, i32 2, i32 3], align 32 ; <[16 x i32]*> [#uses=1]
...
	   %204 = icmp eq i32 %46, 0     

Perl has a bunch of these, also on the 'Perl_regkind' array:
@Perl_yygindex = internal constant [51 x i16] [i16 0, i16 0, i16 0, i16 0, i16 374, i16 351, i16 0, i16 -12, i16 0, i16 946, i16 413, i16 -83, i16 0, i16 0, i16 0, i16 -311, i16 -13, i16 4007, i16 2893, i16 0, i16 0, i16 0, i16 0, i16 0, i16 372, i16 -8, i16 0, i16 0, i16 246, i16 -131, i16 43, i16 86, i16 208, i16 -45, i16 -169, i16 987, i16 0, i16 0, i16 0, i16 0, i16 308, i16 0, i16 -271, i16 0, i16 0, i16 0, i16 0, i16 0, i16 0, i16 0, i16 0], align 32 ; <[51 x i16]*> [#uses=1]
...
  %1364 = icmp eq i16 %1361, 0

186.crafty really likes this on 64-bit machines, because it triggers on a bunch of globals like this:
@white_outpost = internal constant [64 x i8] c"\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\02\02\00\00\00\00\00\04\05\05\04\00\00\00\00\03\06\06\03\00\00\00\00\00\01\01\00\00\00\00\00\00\00\00\00\00\00", align 32 ; <[64 x i8]*> [#uses=2]

However the big winner is 403.gcc, which triggers hundreds of times, eliminating all the accesses to the 57-element arrays 'mode_class', mode_unit_size, mode_bitsize, regclass_map, etc.

go 64-bit machines :)




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92415 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 08:56:52 +00:00
Chris Lattner
34e0c76f93 enhance the previous optimization to work with fcmp in addition
to icmp.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92412 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 08:20:51 +00:00
Chris Lattner
1f12e44b62 Teach instcombine to fold compares of loads from constant
arrays with variable indices into a comparison of the index
with a constant.  The most common occurrence of this that
I see by far is stuff like:

if ("foobar"[i] == '\0') ...

which we compile into: if (i == 6), saving a load and 
materialization of the global address.  This also exposes 
loop trip count information to later passes in many cases.

This triggers hundreds of times in xalancbmk, which is where I first
noticed it, but it also triggers in many other apps.  Here are a few 
interesting ones from various apps:

@must_be_connected_without = internal constant [8 x i8*] [i8* getelementptr inbounds ([3 x i8]* @.str64320, i64 0, i64 0), i8* getelementptr inbounds ([3 x i8]* @.str27283, i64 0, i64 0), i8* getelementptr inbounds ([4 x i8]* @.str71327, i64 0, i64 0), i8* getelementptr inbounds ([4 x i8]* @.str72328, i64 0, i64 0), i8* getelementptr inbounds ([3 x i8]* @.str18274, i64 0, i64 0), i8* getelementptr inbounds ([6 x i8]* @.str11267, i64 0, i64 0), i8* getelementptr inbounds ([3 x i8]* @.str32288, i64 0, i64 0), i8* null], align 32 ; <[8 x i8*]*> [#uses=2]
  %scevgep.i = getelementptr [8 x i8*]* @must_be_connected_without, i64 0, i64 %indvar.i ; <i8**> [#uses=1]
  %17 = load ...
  %18 = icmp eq i8* %17, null                     ; <i1> [#uses=1]
-> icmp eq i64 %indvar.i, 7 


@yytable1095 = internal constant [84 x i8] c"\12\01(\05\06\07\08\09\0A\0B\0C\0D\0E1\0F\10\11266\1D: \10\11,-,0\03'\10\11B6\04\17&\18\1945\05\06\07\08\09\0A\0B\0C\0D\0E\1E\0F\10\11*\1A\1B\1C$3+>#%;<IJ=ADFEGH9KL\00\00\00C", align 32 ; <[84 x i8]*> [#uses=2]
  %57 = getelementptr inbounds [84 x i8]* @yytable1095, i64 0, i64 %56 ; <i8*> [#uses=1]
   %mode.0.in = getelementptr inbounds [9 x i32]* @mb_mode_table, i64 0, i64 %.pn ; <i32*> [#uses=1]
load ...
   %64 = icmp eq i8 %58, 4                         ; <i1> [#uses=1]
-> icmp eq i64 %.pn, 35             ; <i1> [#uses=0]


@gsm_DLB = internal constant [4 x i16] [i16 6554, i16 16384, i16 26214, i16 32767]
%scevgep.i = getelementptr [4 x i16]* @gsm_DLB, i64 0, i64 %indvar.i ; <i16*> [#uses=1]
%425 = load %scevgep.i
%426 = icmp eq i16 %425, -32768                 ; <i1> [#uses=0]
-> false



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92411 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 08:12:04 +00:00
Chris Lattner
0b178e25c4 remove the instcombine transformations that are inserting nasty
pointer to int casts that confuse later optimizations.  See PR3351
for details.

This improves but doesn't complete fix 483.xalancbmk because llvm-gcc
does this xform in GCC's "fold" routine as well.  Clang++ will do
better I guess.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92408 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 00:31:05 +00:00
Chris Lattner
ec12d05019 add a simple instcombine xform, simplify another one to use hasAllZeroIndices()
instead of hand rolling a loop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92403 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 23:09:08 +00:00
Chris Lattner
85c1c964dc generalize the pointer difference optimization to handle
a constantexpr gep on the 'base' side of the expression.
This completes comment #4 in PR3351, which comes from
483.xalancbmk.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92402 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 22:42:29 +00:00
Chris Lattner
f2ebc682d1 teach instcombine to optimize pointer difference idioms involving constant
expressions.  This is a step towards comment #4 in PR3351.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92401 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 22:29:12 +00:00
Chris Lattner
e33d413152 implement the transform requested in PR5284
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92398 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 18:34:40 +00:00
Chris Lattner
d27f911b23 add a few trivial instcombines for llvm.powi.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92383 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 01:52:15 +00:00
Chris Lattner
9506c930aa When factoring multiply expressions across adds, factor both
positive and negative forms of constants together.  This 
allows us to compile:

int foo(int x, int y) {
    return (x-y) + (x-y) + (x-y);
}

into:

_foo:                                                       ## @foo
	subl	%esi, %edi
	leal	(%rdi,%rdi,2), %eax
	ret

instead of (where the 3 and -3 were not factored):

_foo:
        imull   $-3, 8(%esp), %ecx
        imull   $3, 4(%esp), %eax
        addl    %ecx, %eax
        ret

this started out as:
    movl    12(%ebp), %ecx
    imull   $3, 8(%ebp), %eax
    subl    %ecx, %eax
    subl    %ecx, %eax
    subl    %ecx, %eax
    ret

This comes from PR5359.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92381 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 01:13:15 +00:00
Chris Lattner
75954e0bbd test case we alredy get right.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92380 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 00:50:00 +00:00
Chris Lattner
3523993451 reuse negates where possible instead of always creating them from scratch.
This allows us to optimize test12 into:

define i32 @test12(i32 %X) {
  %factor = mul i32 %X, -3                        ; <i32> [#uses=1]
  %Z = add i32 %factor, 6                         ; <i32> [#uses=1]
  ret i32 %Z
}

instead of:

define i32 @test12(i32 %X) {
  %Y = sub i32 6, %X                              ; <i32> [#uses=1]
  %C = sub i32 %Y, %X                             ; <i32> [#uses=1]
  %Z = sub i32 %C, %X                             ; <i32> [#uses=1]
  ret i32 %Z
}



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92373 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-31 20:34:32 +00:00
Chris Lattner
69e98e2c0f teach reassociate to factor x+x+x -> x*3. While I'm at it,
fix RemoveDeadBinaryOp to actually do something.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92368 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-31 19:24:52 +00:00
Chris Lattner
13a754ce92 simple fix for an incorrect factoring which causes a
miscompilation, PR5458.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92354 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-31 08:33:49 +00:00
Chris Lattner
7f4ae5c84c merge some more tests in.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92353 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-31 08:32:22 +00:00
Chris Lattner
e1f5460f78 filecheckize
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92352 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-31 08:29:56 +00:00
Chris Lattner
c17e2849d1 fix two bogus tests that the asmparser now rejects.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92303 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-30 05:54:51 +00:00
Chris Lattner
8047d9a6be move an optimization for memcmp out of simplifylibcalls and into
SDISel.  This optimization was causing simplifylibcalls to 
introduce type-unsafe nastiness.  This is the first step, I'll be 
expanding the memcmp optimizations shortly, covering things that
we really really wouldn't want simplifylibcalls to do.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92098 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-24 00:37:38 +00:00
Bob Wilson
f27a4cd783 Generalize SROA to allow the first index of a GEP to be non-zero. Add a
missing check that an array reference doesn't go past the end of the array,
and remove some redundant checks for in-bound array and vector references
that are no longer needed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91897 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-22 06:57:14 +00:00
Chris Lattner
1a0e7081c3 Implement PR5795 by merging duplicated return blocks. This could go further
by merging all returns in a function into a single one, but simplifycfg 
currently likes to duplicate the return (an unfortunate choice!)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91890 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-22 06:07:30 +00:00
Chris Lattner
42385b03aa convert to filecheck
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91889 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-22 06:04:26 +00:00
Chris Lattner
4c1e3da0cd fix PR5837 by having SSAUpdate reuse phi nodes for the
'GetValueInMiddleOfBlock' case, instead of inserting 
duplicates.

A similar fix is almost certainly needed by the machine-level
SSAUpdate implementation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91820 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-21 07:16:11 +00:00
Chris Lattner
65f067fa63 add check lines for min/max tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91816 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-21 06:08:50 +00:00
Chris Lattner
a0773eb330 really convert this to filecheck.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91815 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-21 06:06:10 +00:00
Chris Lattner
b109b5c148 give instcombine some helper functions for matching MIN and MAX, and
implement some optimizations for MIN(MIN()) and MAX(MAX()) and 
MIN(MAX()) etc.  This substantially improves the code in PR5822 but
doesn't kick in much elsewhere.  2 max's were optimized in 
pairlocalalign and one in smg2000.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91814 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-21 06:03:05 +00:00
Chris Lattner
a278d4a1f7 filecheckize
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91813 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-21 05:53:13 +00:00
Chris Lattner
3bf6815556 enhance x-(-A) -> x+A to preserve NUW/NSW.
Use the presence of NSW/NUW to fold "icmp (x+cst), x" to a constant in
cases where it would otherwise be undefined behavior.

Surprisingly (to me at least), this triggers hundreds of the times in
a few benchmarks: lencode, ldecode, and 466.h264ref seem to *really*
like this.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91812 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-21 04:04:05 +00:00
Chris Lattner
2799bafb98 Optimize all cases of "icmp (X+Cst), X" to something simpler. This triggers
a bunch in lencode, ldecod, spass, 176.gcc, 252.eon, among others.  It is 
also the first part of PR5822


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91811 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-21 03:19:28 +00:00
Chris Lattner
6b57a797ab convert to filecheck
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91810 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-21 03:11:05 +00:00
Chris Lattner
f648125be9 fix an overly conservative caching issue that caused memdep to
cache a pointer as being unavailable due to phi trans in the
wrong place.  This would cause later queries to fail even when
they didn't involve phi trans.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91787 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-19 21:29:22 +00:00
Chris Lattner
16e7ae42a1 fix inconsistent use of tabs
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91783 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-19 20:44:43 +00:00
Chris Lattner
0ebc6ce974 fix PR5827 by disabling the phi slicing transformation in a case
where instcombine would have to split a critical edge due to a
phi node of an invoke.  Since instcombine can't change the CFG,
it has to bail out from doing the transformation.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91763 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-19 07:01:15 +00:00
Bob Wilson
b742defa0a Reapply 91459 with a simple fix for the problem that broke the x86_64-darwin
bootstrap.  This also replaces the WeakVH references that Chris objected to
with normal Value references.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91711 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-18 20:14:40 +00:00
Eli Friedman
97b087c778 Optimize icmp of null and select of two constants even if the select has
multiple uses.  (The construct in question was found in gcc.)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91675 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-18 08:22:35 +00:00
Eli Friedman
b17cb06c35 Allow instcombine to combine "sext(a) >u const" to "a >u trunc(const)".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91631 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-17 22:42:29 +00:00
Eli Friedman
8e4b197e0b Make the ptrtoint comparison simplification work if one side is a global.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91624 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-17 21:27:47 +00:00
Eli Friedman
0c826d98b3 Slightly generalize transformation of memmove(a,a,n) so that it also applies
to memcpy. (Such a memcpy is technically illegal, but in practice is safe
and is generated by struct self-assignment in C code.)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91621 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-17 21:07:31 +00:00
Bob Wilson
39c88a641b Re-revert 91459. It's breaking the x86_64 darwin bootstrap.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91607 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-17 18:34:24 +00:00
Eli Friedman
e8e17833be Aggressively flip compare constant expressions where appropriate; constant
folding in particular expects null to be on the RHS.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91587 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-17 06:07:04 +00:00
Daniel Dunbar
2674089cef Reapply r91459, it was only unmasking the bug, and since TOT is still broken having it reverted does no good.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91559 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-16 20:09:53 +00:00
Daniel Dunbar
fca55c8ac7 Revert "Reapply 91184 with fixes and an addition to the testcase to cover the
problem", this broke llvm-gcc bootstrap for release builds on
x86_64-apple-darwin10.

This reverts commit db22309800b224a9f5f51baf76071d7a93ce59c9.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91534 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-16 10:56:17 +00:00
Chris Lattner
24604110ef reapply my strstr optimization. I have reproduced the x86-64 bootstrap
miscompile (i386.o miscompares) but it happens both with and without
this patch.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91532 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-16 09:32:05 +00:00
Chris Lattner
0001517d9d revert my strstr optimization, I'm told it breaks x86-64 bootstrap.
Will reapply with a fix when I get a chance.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91486 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-16 00:46:02 +00:00
Bob Wilson
970eaf2520 Reapply 91184 with fixes and an addition to the testcase to cover the problem
found last time.  Instead of trying to modify the IR while iterating over it,
I've change it to keep a list of WeakVH references to dead instructions, and
then delete those instructions later.  I also added some special case code to
detect and handle the situation when both operands of a memcpy intrinsic are
referencing the same alloca.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91459 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-15 22:00:51 +00:00
Chris Lattner
ad6b1fdaf9 optimize strstr, PR5783
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91438 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-15 19:14:40 +00:00
Eric Christopher
38e1074c53 Add radar fixed in comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91312 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-14 19:07:25 +00:00
Shantonu Sen
bc1c99c4fb Remove empty file completely
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91277 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-14 14:15:15 +00:00
Chris Lattner
a59adc4015 revert r91184, because it causes a crash on a .bc file I just
sent to Bob.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91268 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-14 05:11:02 +00:00
Benjamin Kramer
7b3f1a21ea Fix some CHECK lines which were ignored by accident.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91214 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-12 09:25:50 +00:00
Bob Wilson
73a1b67cb9 Revise scalar replacement to be more flexible about handle bitcasts and GEPs.
While scanning through the uses of an alloca, keep track of the current offset
relative to the start of the alloca, and check memory references to see if
the offset & size correspond to a component within the alloca.  This has the
nice benefit of unifying much of the code from isSafeUseOfAllocation,
isSafeElementUse, and isSafeUseOfBitCastedAllocation.  The code to rewrite
the uses of a promoted alloca, after it is determined to be safe, is
reorganized in the same way.

Also, when rewriting GEP instructions, mark them as "in-bounds" since all the
indices are known to be safe.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91184 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-11 23:47:40 +00:00
Dan Gohman
050959cd08 Make getUniqueExitBlocks's precondition assert more precise, to
avoid spurious failures. This fixes PR5758.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91147 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-11 20:05:23 +00:00
Eric Christopher
072f6fe196 Add a test for the fix in revision 91009.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91062 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-10 21:11:40 +00:00
Chris Lattner
16f244e982 Fix PR5744, a case where we were getting the pointer size instead of the
value size.  This only manifested when memdep inprecisely returns clobber,
which is do to a caching issue in the PR5744 testcase.  We can 'efficiently
emulate' this by using '-no-aa'


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91004 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-10 00:11:45 +00:00
Chris Lattner
af064aeee6 fix hte last remaining known (by me) phi translation bug. When we reanalyze
clobbers to forward pieces of large stores to small loads, we need to consider
the properly phi translated pointer in the store block.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90978 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-09 18:21:46 +00:00
Chris Lattner
4d3a16f81b Add a minor optimization: if we haven't changed the operands of an
add, there is no need to scan the world to find the same add again.
This invalidates the previous testcase, which wasn't wonderful anyway,
because it needed a run of instcombine to permute the use-lists in 
just the right way to before GVN was run (so it was really fragile).
Not a big loss.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90973 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-09 17:27:45 +00:00
Chris Lattner
eddc65aa0d fix PR5733, a case where we'd replace an add with a lexically identical
binary operator that wasn't an add.  In this case, a xor.  Whoops.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90971 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-09 17:18:49 +00:00
Chris Lattner
1a247f32dd merge crash-2.ll into crash.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90969 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-09 17:17:26 +00:00
Chris Lattner
55fe79f044 the code in GVN that tries to forward large loads to small
stores is not phi translating, thus it miscompiles really
crazy testcases.  This is from inspection, I haven't seen
this in the wild.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90930 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-09 02:43:05 +00:00
Chris Lattner
05e15f8897 Switch GVN and memdep to use PHITransAddr, which correctly handles
phi translation of complex expressions like &A[i+1].  This has the
following benefits:

1. The phi translation logic is all contained in its own class with
   a strong interface and verification that it is self consistent.

2. The logic is more correct than before.  Previously, if intermediate
   expressions got PHI translated, we'd miss the update and scan for
   the wrong pointers in predecessor blocks.  @phi_trans2 is a testcase
   for this.

3. We have a lot less code in memdep.

We can handle phi translation across blocks of things like @phi_trans3,
which is pretty insane :).

This patch should fix the miscompiles of 255.vortex, and I tested it 
with a bootstrap of llvm-gcc, llvm-test and dejagnu of course.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90926 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-09 01:59:31 +00:00
Duncan Sands
7a154cf228 Teach GlobalOpt to delete aliases with internal linkage (after
forwarding any uses).  GlobalDCE can also do this, but is only
run at -O3.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90850 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-08 10:10:20 +00:00
Chris Lattner
08bc2701a2 fix PR5698
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90708 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-06 17:17:23 +00:00
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
Nick Lewycky
83e8ec73e1 Generalize this optimization to work on equality comparisons between any two
integers that are constant except for a single bit (the same n-th bit in each).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90646 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-05 05:00:00 +00:00
Chris Lattner
44a7a380aa Fix PR5551 by not ignoring the top level constantexpr when
folding a load from constant.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90545 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-04 06:29:29 +00:00