Commit Graph

55919 Commits

Author SHA1 Message Date
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
Chris Lattner
1c91fae649 theoretically the negate we find could be in a different function, check
for this case.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92425 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 21:46:33 +00:00
Chris Lattner
82602bc089 use enums for the over/underdefined markers for clarity. Switch
to using -2/-3 instead of -1/-2 for a future xform.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92423 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 20:20:33 +00:00
Chris Lattner
5fadf17709 remove the random sampling framework, which is not maintained anymore.
If there is interest, it can be resurrected from SVN.  PR4912.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92422 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 20:07:03 +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
33a1ec76c2 fix a miscompilation I introduced of cdecl with a late change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92416 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 09:22:13 +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
Mikhail Glushenkov
364cf75c40 Forward -O0 to llvm-gcc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92414 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 08:27:23 +00:00
Mikhail Glushenkov
bc56d86e25 Apparently, it is OK for -MT to be specified several times.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92413 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 08:27:10 +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
79fa3cf451 constant fold nasty constant expressions formed by llvm-gcc,
wrapping up PR3351.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92410 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 01:22:23 +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
09987f73f6 allow this to work on linux hosts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92407 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 00:22:15 +00:00
Chris Lattner
133ce871df Teach codegen to handle:
(X != null) | (Y != null) --> (X|Y) != 0
 (X == null) & (Y == null) --> (X|Y) == 0

so that instcombine can stop doing this for pointers.  This is part of PR3351,
which is a case where instcombine doing this for pointers (inserting ptrtoint)
is pessimizing code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92406 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-02 00:00:03 +00:00
Chris Lattner
aac00392c3 rename file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92405 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 23:55:04 +00:00
Chris Lattner
53334ca5ac whitespace cleanup
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92404 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 23:37:34 +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
3376718505 use 'match' to simplify some code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92400 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 22:12:03 +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
Mikhail Glushenkov
bfdfea86a1 Fix a warning on gcc 4.4.
SelectionDAGBuilder.cpp:4294: warning: suggest explicit braces to avoid
ambiguous ‘else’

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92395 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 04:41:36 +00:00
Mikhail Glushenkov
b3c0199f6a Trailing whitespace, 80-col violations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92394 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 04:41:22 +00:00
Mikhail Glushenkov
99da5d7bba Minor simplifactions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92393 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 04:41:10 +00:00
Mikhail Glushenkov
b7935e00eb Typo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92392 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 04:40:54 +00:00
Mikhail Glushenkov
d64c90776e Make CheckForSuperfluousOptions handle list form of 'switch_on' correctly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92391 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 03:51:02 +00:00
Mikhail Glushenkov
3a481e38c9 Minor simplifications.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92390 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 03:50:51 +00:00
Mikhail Glushenkov
163dd597c9 Better error message.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92389 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 03:50:34 +00:00
Chris Lattner
f031e8ad01 Teach codegen to lower llvm.powi to an efficient (but not optimal)
multiply sequence when the power is a constant integer.  Before, our
codegen for std::pow(.., int) always turned into a libcall, which was
really inefficient.

This should also make many gfortran programs happier I'd imagine.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92388 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 03:32:16 +00:00
Chris Lattner
0fba8cf9ff Make this more likely to generate a libcall.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92387 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 03:26:51 +00:00
Chris Lattner
f9ead87c68 add missing line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92384 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 01:54:08 +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
398ffba75f update this. To take the next step, llvm.powi should be generalized to work
on integers as well and codegen should lower them to branch trees.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92382 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 01:29:26 +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
Ted Kremenek
371da99e64 Remove old header.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92378 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 00:04:49 +00:00
Chris Lattner
9046193e55 clean up some comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92377 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 00:04:26 +00:00
Chris Lattner
f55e7f54b1 switch from std::map to DenseMap for rank data structures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92375 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-01 00:01:34 +00:00
Ted Kremenek
43afbce8ba Remove derelict serialization code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92374 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-31 23:40:17 +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
f31e2e92a8 we don't need a smallptrset to detect duplicates, the values are
sorted, so we can just do a linear scan.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92372 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-31 19:49:01 +00:00
Chris Lattner
1e7558b656 make reassociate more careful about not leaving around dead mul's
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92370 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-31 19:34:45 +00:00
Chris Lattner
f8a447de16 remove debug
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92369 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-31 19:25:19 +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
9f7b7089be change reassociate to use SmallVector for its key datastructures
instead of std::vector.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92366 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-31 18:40:32 +00:00
Chris Lattner
9cd1bc4f8b change an if to an assert, fix comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92364 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-31 18:18:46 +00:00
Chris Lattner
94285e620b move the rest of the add optimization code out to OptimizeAdd,
improve some comments, simplify a bit of code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92363 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-31 18:17:13 +00:00