Commit Graph

1188 Commits

Author SHA1 Message Date
Chris Lattner
01575b7315 Turn (cast (shuffle (cast)) -> shuffle (cast) if it reduces the # casts in
the program.  This exposes more opportunities for the instcombiner, and implements
vec_shuffle.ll:test6


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28487 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-25 23:24:33 +00:00
Chris Lattner
73fa49d697 extract element from a shuffle vector can be trivially turned into an
extractelement from the SV's source.  This implement vec_shuffle.ll:test[45]


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28485 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-25 22:53:38 +00:00
Chris Lattner
01859e8853 Silence a bogus gcc warning
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28422 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-20 23:14:03 +00:00
Evan Cheng
3e246dd084 Backing out last check-in for now. It's causing an infinite loop gccas lencode.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28284 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-14 06:46:03 +00:00
Chris Lattner
033aaaf451 Add/Sub/Mul are safe to promote here as well. Incrementing a single-bit
bitfield now gives this code:

_plus:
        lwz r2, 0(r3)
        rlwimi r2, r2, 0, 1, 31
        xoris r2, r2, 32768
        stw r2, 0(r3)
        blr

instead of this:

_plus:
        lwz r2, 0(r3)
        srwi r4, r2, 31
        slwi r4, r4, 31
        addis r4, r4, -32768
        rlwimi r2, r4, 0, 0, 0
        stw r2, 0(r3)
        blr

this can obviously still be improved.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28275 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-13 02:16:08 +00:00
Chris Lattner
70074e00a2 Implement simple promotion for cast elimination in instcombine. This is
currently very limited, but can be extended in the future.  For example,
we now compile:

uint %test30(uint %c1) {
        %c2 = cast uint %c1 to ubyte
        %c3 = xor ubyte %c2, 1
        %c4 = cast ubyte %c3 to uint
        ret uint %c4
}

to:

_xor:
        movzbl 4(%esp), %eax
        xorl $1, %eax
        ret

instead of:

_xor:
        movb $1, %al
        xorb 4(%esp), %al
        movzbl %al, %eax
        ret

More impressively, we now compile:

struct B { unsigned bit : 1; };
void xor(struct B *b) { b->bit = b->bit ^ 1; }

To (X86/PPC):

_xor:
        movl 4(%esp), %eax
        xorl $-2147483648, (%eax)
        ret
_xor:
        lwz r2, 0(r3)
        xoris r2, r2, 32768
        stw r2, 0(r3)
        blr

instead of (X86/PPC):

_xor:
        movl 4(%esp), %eax
        movl (%eax), %ecx
        movl %ecx, %edx
        shrl $31, %edx
        # TRUNCATE movb %dl, %dl
        xorb $1, %dl
        movzbl %dl, %edx
        andl $2147483647, %ecx
        shll $31, %edx
        orl %ecx, %edx
        movl %edx, (%eax)
        ret

_xor:
        lwz r2, 0(r3)
        srwi r4, r2, 31
        xori r4, r4, 1
        rlwimi r2, r4, 31, 0, 0
        stw r2, 0(r3)
        blr

This implements InstCombine/cast.ll:test30.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28273 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-13 02:06:03 +00:00
Chris Lattner
8c8c66a8cd Refactor some code, making it simpler.
When doing the initial pass of constant folding, if we get a constantexpr,
simplify the constant expr like we would do if the constant is folded in the
normal loop.

This fixes the missed-optimization regression in
Transforms/InstCombine/getelementptr.ll last night.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28224 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-11 17:11:52 +00:00
Chris Lattner
f4f5a77fdc Two changes:
1. Implement InstCombine/deadcode.ll by not adding instructions in unreachable
   blocks (due to constants in conditional branches/switches) to the worklist.
   This causes them to be deleted before instcombine starts up, leading to
   better optimization.

2. In the prepass over instructions, do trivial constprop/dce as we go.  This
   has the effect of improving the effectiveness of #1.  In addition, it
   *significantly* speeds up instcombine on test cases with large amounts of
   constant folding code (for example, that produced by code specialization
   or partial evaluation).  In one example, it speeds up instcombine from
   0.0589s to 0.0224s with a release build (a 2.6x speedup).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28215 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-10 19:00:36 +00:00
Chris Lattner
33a6113995 Move some code around.
Make the "fold (and (cast A), (cast B)) -> (cast (and A, B))" transformation
only apply when both casts really will cause code to be generated.  If one or
both doesn't, then this xform doesn't remove a cast.

This fixes Transforms/InstCombine/2006-05-06-Infloop.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28141 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-06 09:00:16 +00:00
Chris Lattner
581a7ad7c9 Fix an infinite loop compiling oggenc last night.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28128 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-05 20:51:30 +00:00
Chris Lattner
6fc205fc44 Implement InstCombine/cast.ll:test29
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28126 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-05 06:39:07 +00:00
Chris Lattner
e3158308e0 Fix Transforms/InstCombine/2006-05-04-DemandedBitCrash.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28101 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-04 17:33:35 +00:00
Chris Lattner
94046b4d10 Fix InstCombine/2006-04-28-ShiftShiftLongLong.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28019 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-28 22:21:41 +00:00
Chris Lattner
ae74f55552 Fix Transforms/Reassociate/2006-04-27-ReassociateVector.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28007 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-28 04:14:49 +00:00
Chris Lattner
d929f06f4d Add support for inserting undef into a vector. This implements
Transforms/InstCombine/vec_insert_to_shuffle.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27997 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-27 21:14:21 +00:00
Chris Lattner
df4f226cdc Fix Transforms/ScalarRepl/2006-04-20-PromoteCrash.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27912 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-20 20:48:50 +00:00
Andrew Lenharth
7a31b975fb Make code match cvs commit message :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27881 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-20 15:41:37 +00:00
Andrew Lenharth
8117f9a40e If we can convert the return pointer type into an integer that IntPtrType
can be converted to losslessly, we can continue the conversion to a direct call.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27880 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-20 14:56:47 +00:00
Chris Lattner
fd6bdf0b0f Turn x86 unaligned load/store intrinsics into aligned load/store instructions
if the pointer is known aligned.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27781 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-17 22:26:56 +00:00
Chris Lattner
7f6cc0ccb5 Fix a bug in the 'shuffle(undef,x,mask) -> shuffle(x, undef,mask')' xform
Make the insert/extract elt -> shuffle code more aggressive.

This fixes CodeGen/PowerPC/vec_shuffle.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27728 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-16 00:51:47 +00:00
Chris Lattner
706126dac1 Canonicalize shuffle(undef,x,mask) -> shuffle(x, undef,mask').
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27727 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-16 00:03:56 +00:00
Chris Lattner
efb47359ff significant cleanups to code that uses insert/extractelt heavily. This builds
maximal shuffles out of them where possible.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27717 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-15 01:39:45 +00:00
Chris Lattner
de6df88529 Teach scalarrepl to promote unions of vectors and floats, producing
insert/extractelement operations.  This implements
Transforms/ScalarRepl/vector_promote.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27710 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-14 21:42:41 +00:00
Reid Spencer
ad2072643a Get rid of a signed/unsigned compare warning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27625 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-12 19:28:15 +00:00
Chris Lattner
9fb9213083 Turn casts into getelementptr's when possible. This enables SROA to be more
aggressive in some cases where LLVMGCC 4 is inserting casts for no reason.

This implements InstCombine/cast.ll:test27/28.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27620 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-12 18:09:35 +00:00
Chris Lattner
389a6f58f7 Implement vec_shuffle.ll:test3
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27573 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-10 23:06:36 +00:00
Chris Lattner
a844fc4cb0 Implement InstCombine/vec_shuffle.ll:test[12]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27571 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-10 22:45:52 +00:00
Chris Lattner
543abdf1d0 Add supprot for shufflevector
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27513 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-08 01:19:12 +00:00
Chris Lattner
e2ed057562 Lower vperm(x,y, mask) -> shuffle(x,y,mask) if mask is constant. This allows
us to compile oh-so-realistic stuff like this:

 vec_vperm(A, B, (vector unsigned char){14});

to:
        vspltb v0, v0, 14

instead of:

        vspltisb v0, 14
        vperm v0, v2, v1, v0


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27452 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-06 19:19:17 +00:00
Chris Lattner
4132afb0d2 vector casts of casts are eliminable. Transform this:
%tmp = cast <4 x uint> %tmp to <4 x int>                ; <<4 x int>> [#uses=1]
        %tmp = cast <4 x int> %tmp to <4 x float>               ; <<4 x float>> [#uses=1]

into:

        %tmp = cast <4 x uint> %tmp to <4 x float>              ; <<4 x float>> [#uses=1]


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27355 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-02 05:43:13 +00:00
Chris Lattner
a1c3538537 Allow transforming this:
%tmp = cast <4 x uint>* %testData to <4 x int>*         ; <<4 x int>*> [#uses=1]
        %tmp = load <4 x int>* %tmp             ; <<4 x int>> [#uses=1]

to this:

        %tmp = load <4 x uint>* %testData               ; <<4 x uint>> [#uses=1]
        %tmp = cast <4 x uint> %tmp to <4 x int>                ; <<4 x int>> [#uses=1]


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27353 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-02 05:37:12 +00:00
Chris Lattner
82ed58f9c4 Turn altivec lvx/stvx intrinsics into loads and stores. This allows the
elimination of one load from this:

int AreSecondAndThirdElementsBothNegative( vector float *in ) {
#define QNaN 0x7FC00000
const vector unsigned int testData = (vector unsigned int)( QNaN, 0, 0, QNaN );
vector float test = vec_ld( 0, (float*) &testData );
return ! vec_any_ge( test, *in );
}

Now generating:

_AreSecondAndThirdElementsBothNegative:
        mfspr r2, 256
        oris r4, r2, 49152
        mtspr 256, r4
        li r4, lo16(LCPI1_0)
        lis r5, ha16(LCPI1_0)
        addi r6, r1, -16
        lvx v0, r5, r4
        stvx v0, 0, r6
        lvx v1, 0, r3
        vcmpgefp. v0, v0, v1
        mfcr r3, 2
        rlwinm r3, r3, 27, 31, 31
        xori r3, r3, 1
        cntlzw r3, r3
        srwi r3, r3, 5
        mtspr 256, r2
        blr


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27352 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-02 05:30:25 +00:00
Chris Lattner
ae1ab3989c Fix InstCombine/2006-04-01-InfLoop.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27330 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-01 22:05:01 +00:00
Chris Lattner
64daab56c2 Fold A^(B&A) -> (B&A)^A
Fold (B&A)^A == ~B & A

This implements InstCombine/xor.ll:test2[56]


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27328 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-01 08:03:55 +00:00
Chris Lattner
6e6b0da303 If we can look through vector operations to find the scalar version of an
extract_element'd value, do so.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27323 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-31 23:01:56 +00:00
Chris Lattner
1f13c88939 extractelement(undef,x) -> undef
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27300 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-31 18:25:14 +00:00
Chris Lattner
df084ff78b Fix Transforms/InstCombine/2006-03-30-ExtractElement.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27261 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-30 22:02:40 +00:00
Chris Lattner
98509ef3c7 Don't crash on packed logical ops
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27125 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-25 21:58:26 +00:00
Chris Lattner
98d9811db2 Fix spello
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27052 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-24 07:14:34 +00:00
Chris Lattner
0f862e50ae add the actual cost to the debug info
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27051 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-24 07:14:00 +00:00
Jim Laskey
930ac0606c Can't combine anymore - we don't have a chain through llvm.dbg intrinsics.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26992 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-23 18:10:42 +00:00
Chris Lattner
035c6a2356 silence a bogus gcc warning
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26953 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-22 17:27:24 +00:00
Chris Lattner
273f202890 Teach cee to propagate through switch statements. This implements
Transforms/CorrelatedExprs/switch.ll

Patch contributed by Eric Kidd!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26872 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-19 19:37:24 +00:00
Evan Cheng
21495775e7 - Fixed a bogus if condition.
- Added more debugging info.
- Allow reuse of IV of negative stride. e.g. -4 stride == 2 * iv of -2 stride.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26841 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-18 08:03:12 +00:00
Evan Cheng
4496a50deb Sort StrideOrder so we can process the smallest strides first. This allows
for more IV reuses.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26837 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-18 00:44:49 +00:00
Evan Cheng
eb8f9e2297 Allow users of iv / stride to be rewritten with expression that is a multiply
of a smaller stride even if they have a common loop invariant expression part.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26828 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-17 19:52:23 +00:00
Evan Cheng
d1d6b5cce2 For each loop, keep track of all the IV expressions inserted indexed by
stride. For a set of uses of the IV of a stride which is a multiple
of another stride, do not insert a new IV expression. Rather, reuse the
previous IV and rewrite the uses as uses of IV expression multiplied by
the factor.

e.g.
x = 0 ...; x ++
y = 0 ...; y += 4
then use of y can be rewritten as use of 4*x for x86.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26803 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-16 21:53:05 +00:00
Chris Lattner
e9efecbf47 Implement a FIXME, recusively reassociating
A*A*B + A*A*C   -->   A*(A*B+A*C)   -->   A*(A*(B+C))

This implements Reassociate/mul-factor3.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26757 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-14 16:04:29 +00:00
Chris Lattner
895b392269 extract some code into a method, no functionality change
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26755 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-14 07:11:11 +00:00
Chris Lattner
22a66c41f3 Promote shifts by a constant to multiplies so that we can reassociate
(x<<1)+(y<<1) -> (X+Y)<<1.  This implements
Transforms/Reassociate/shift-factor.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26753 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-14 06:55:18 +00:00
Evan Cheng
d277f2c669 Added target lowering hooks which LSR consults to make more intelligent
transformation decisions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26738 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-13 23:14:23 +00:00
Chris Lattner
25de486263 Fix a miscompilation of 188.ammp with the new CFE. 188.ammp is accessing
arrays out of range in a horrible way, but we shouldn't break it anyway.
Details in the comments.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26606 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-08 01:05:29 +00:00
Chris Lattner
51c26e911a Teach the alignment handling code to look through constant expr casts and GEPs
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26580 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-07 01:28:57 +00:00
Chris Lattner
95a959dc1a Teach instcombine to increase the alignment of memset/memcpy/memmove when
the pointer is known to come from either a global variable, alloca or
malloc.  This allows us to compile this:

  P = malloc(28);
  memset(P, 0, 28);

into explicit stores on PPC instead of a memset call.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26577 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-06 20:18:44 +00:00
Chris Lattner
220b0cf3e4 Make vector narrowing more effective, implementing
Transforms/InstCombine/vec_narrow.ll.  This add support for narrowing
extract_element(insertelement) also.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26538 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-05 00:22:33 +00:00
Chris Lattner
e5022fe4cd Add factoring of multiplications, e.g. turning A*A+A*B into A*(A+B).
Testcase here: Transforms/Reassociate/mulfactor.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26524 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-04 09:31:13 +00:00
Chris Lattner
ab51f3fa96 Canonicalize (X+C1)*C2 -> X*C2+C1*C2
This implements Transforms/InstCombine/add.ll:test31


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26519 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-04 06:04:02 +00:00
Chris Lattner
21959390c1 Change this to work with renamed intrinsics.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26484 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-03 01:34:17 +00:00
Chris Lattner
db3f873bd8 Generalize the REM folding code to handle another case Nick Lewycky
pointed out: realize the AND can provide factors and look through Casts.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26469 91177308-0d34-0410-b5e6-96231b3b80d8
2006-03-02 06:50:58 +00:00
Chris Lattner
06e1e25368 Fix a regression in a patch from a couple of days ago. This fixes
Transforms/InstCombine/2006-02-28-Crash.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26427 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-28 19:47:20 +00:00
Chris Lattner
9794392781 Implement rem.ll:test[7-9] and PR712
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26415 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-28 05:49:21 +00:00
Chris Lattner
6c9951b0da Simplify some code now that the RHS of a rem can't be 0
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26413 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-28 05:40:55 +00:00
Chris Lattner
19ccd5c757 Rearrange some code, fold "rem X, 0", implementing rem.ll:test6
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26411 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-28 05:30:45 +00:00
Chris Lattner
3e88a4d700 Merge two almost-identical pieces of code.
Make this code more powerful by using ComputeMaskedBits instead of looking
for an AND operand.  This lets us fold this:

int %test23(int %a) {
        %tmp.1 = and int %a, 1
        %tmp.2 = seteq int %tmp.1, 0
        %tmp.3 = cast bool %tmp.2 to int  ;; xor tmp1, 1
        ret int %tmp.3
}

into: xor (and a, 1), 1


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26396 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-27 02:38:23 +00:00
Chris Lattner
26ab9a9218 Fold (A^B) == A -> B == 0
and  (A-B) == A  ->  B == 0


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26394 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-27 01:44:11 +00:00
Chris Lattner
02bd1b3e94 Fold (X|C1)^C2 -> X^(C1|C2) when possible. This implements
InstCombine/or.ll:test23.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26385 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-26 19:57:54 +00:00
Chris Lattner
97f37a439c Fix a problem that Nate noticed that boils down to an over conservative check
in the code that does "select C, (X+Y), (X-Y) --> (X+(select C, Y, (-Y)))".
We now compile this loop:

LBB1_1: ; no_exit
        add r6, r2, r3
        subf r3, r2, r3
        cmpwi cr0, r2, 0
        addi r7, r5, 4
        lwz r2, 0(r5)
        addi r4, r4, 1
        blt cr0, LBB1_4 ; no_exit
LBB1_3: ; no_exit
        mr r3, r6
LBB1_4: ; no_exit
        cmpwi cr0, r4, 16
        mr r5, r7
        bne cr0, LBB1_1 ; no_exit

into this instead:

LBB1_1: ; no_exit
        srawi r6, r2, 31
        add r2, r2, r6
        xor r6, r2, r6
        addi r7, r5, 4
        lwz r2, 0(r5)
        addi r4, r4, 1
        add r3, r3, r6
        cmpwi cr0, r4, 16
        mr r5, r7
        bne cr0, LBB1_1 ; no_exit


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26356 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-24 18:05:58 +00:00
Chris Lattner
f8bf116f80 Fix Regression/Transforms/LoopUnswitch/2006-02-22-UnswitchCrash.ll, which
caused SPASS to fail building last night.

We can't trivially unswitch a loop if the exit block has phi nodes in it,
because we don't know which predecessor to use.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26320 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-22 23:55:00 +00:00
Chris Lattner
bd28e3f8ef Add some comments, simplify some code, and fix a bug that caused rewriting
to rewrite with the wrong value.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26311 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-22 06:37:14 +00:00
Chris Lattner
a6fc94b71e improved support for branch folding, still not enabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26289 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-18 07:57:38 +00:00
Jeff Cohen
bce4805d6f Fix bugs identified by VC++.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26287 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-18 03:20:33 +00:00
Chris Lattner
db41024a85 Implement deletion of dead blocks, currently disabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26285 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-18 02:42:34 +00:00
Chris Lattner
caf4893536 a previous patch completely disabled trivial unswitching, this fixees it.
Thanks to nate for pointing this out :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26280 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-18 01:32:04 +00:00
Chris Lattner
f4412d890d initial trivial support for folding branches that have now-constant destinations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26279 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-18 01:27:45 +00:00
Chris Lattner
25cae0fd1c When unswitching a loop, make sure to update loop info with exit blocks in
the right loop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26277 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-18 00:55:32 +00:00
Chris Lattner
0017d480cc Fix loops where the header has an exit, fixing a loop-unswitch crash on crafty
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26258 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-17 06:39:56 +00:00
Chris Lattner
52221f7b16 start of some new simplification code, not thoroughly tested, use at your own
risk :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26248 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-17 00:31:07 +00:00
Nate Begeman
368e18d56a Rework the SelectionDAG-based implementations of SimplifyDemandedBits
and ComputeMaskedBits to match the new improved versions in instcombine.
Tested against all of multisource/benchmarks on ppc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26238 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-16 21:11:51 +00:00
Chris Lattner
10cd9bbde7 Change SplitBlock to increment a BasicBlock::iterator, not an Instruction*. Apparently they do different things :)
This fixes a testcase that nate reduced from spass.

Also included are a couple minor code changes that don't affect the generated
code at all.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26235 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-16 19:36:22 +00:00
Jeff Cohen
21c107ab0f Fix VC++ warning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26228 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-16 04:07:37 +00:00
Chris Lattner
f17c42d409 fix a bug where we unswitched the wrong way
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26225 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-16 01:24:41 +00:00
Chris Lattner
a48654ef23 Implement trivial unswitching for switch stmts. This allows us to trivial
unswitch this loop on 2 before sweating to unswitch on 1/3.

void test4(int N, int i, int C, int*P, int*Q) {
  int j;
  for (j = 0; j < N; ++j) {
    switch (C) {                // general unswitching.
    default: P[i+j] = 0; break;
    case 1: Q[i+j] = 0; break;
    case 3: P[i+j] = Q[i+j]; break;
    case 2: break;              //  TRIVIAL UNSWITCH on C==2
    }
  }
}


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26223 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-15 22:52:05 +00:00
Chris Lattner
4e1323969c make "trivial" unswitching significantly more general. It can now handle
this for example:

  for (j = 0; j < N; ++j) {     // trivial unswitch
    if (C)
      P[i+j] = 0;
  }

turning it into the obvious code without bothering to duplicate an empty loop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26220 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-15 22:03:36 +00:00
Chris Lattner
3fdde110eb Checking the wrong value. This caused us to emit silly code like
Y = seteq bool X, true
instead of just using X :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26215 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-15 19:05:52 +00:00
Chris Lattner
6d9d13d2e4 more refactoring, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26194 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-15 01:44:42 +00:00
Chris Lattner
fed5d9dbd3 pull some code out into a function
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26191 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-15 00:07:43 +00:00
Chris Lattner
3dd4c402de Use statistics to keep track of what flavors of loops we are unswitching
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26157 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-14 01:01:41 +00:00
Chris Lattner
2082ad9b41 Implement Instcombine/and.ll:test34
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26155 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-13 23:07:23 +00:00
Chris Lattner
f345fe4d9a If any of the sign extended bits are demanded, the input sign bit is demanded
for a sign extension.

This fixes InstCombine/2006-02-13-DemandedMiscompile.ll and Ptrdist/bc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26152 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-13 22:41:07 +00:00
Chris Lattner
c15637bafc Be careful not to request or look at bits shifted in from outside the size
of the input.  This fixes the mediabench/gsm/toast failure last night.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26138 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-13 06:09:08 +00:00
Chris Lattner
8d6bbdbbcb remove some more dead special case code
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26135 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-12 08:07:37 +00:00
Chris Lattner
f8c36f502b Eliminate special case hacks that are superceded by general purpose hacks
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26134 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-12 08:02:11 +00:00
Chris Lattner
bf5d8a8270 Three changes:
1. Teach GetConstantInType to handle boolean constants.
2. Teach instcombine to fold (compare X, CST) when X has known 0/1 bits.
   Testcase here: set.ll:test22
3. Improve the "(X >> c1) & C2 == 0" folding code to allow a noop cast
   between the shift and and.  More aggressive bitfolding for other reasons
   was turning signed shr's into unsigned shr's, leaving the noop cast in
   the way.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26131 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-12 02:07:56 +00:00
Chris Lattner
255d8919b6 Port the recent innovations in ComputeMaskedBits to SimplifyDemandedBits.
This allows us to simplify on conditions where bits are not known, but they
are not demanded either!  This also fixes a couple of bugs in
ComputeMaskedBits that were exposed during this work.

In the future, swaths of instcombine should be removed, as this code
subsumes a bunch of ad-hockery.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26122 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-11 09:31:47 +00:00
Chris Lattner
c23580969f implement unswitching of loops with switch stmts and selects in them
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26114 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-11 00:43:37 +00:00
Chris Lattner
e825593bf2 Update PHI nodes in successors of exit blocks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26113 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-10 23:26:14 +00:00
Chris Lattner
b2bc315eac Reform the unswitching code in terms of edge splitting, not block splitting.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26112 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-10 23:16:39 +00:00
Chris Lattner
81be2e961b Fix a case where UnswitchTrivialCondition broke critical edges with
phi's in the successors


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26108 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-10 19:08:15 +00:00
Chris Lattner
708e1a5c9c add some notes, move some code around. Implement unswitching of loops
with branches on partially invariant computations.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26104 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-10 02:30:37 +00:00
Chris Lattner
dd3ee6d086 Move code around to be more logical, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26103 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-10 02:01:22 +00:00