Commit Graph

1134 Commits

Author SHA1 Message Date
Chris Lattner
2d8551c85b Delete dead loads in the dag. This allows us to compile
vector.ll:test_extract_elt2 into:

_test_extract_elt2:
        lfd f1, 32(r3)
        blr

instead of:

_test_extract_elt2:
        lfd f0, 56(r3)
        lfd f0, 48(r3)
        lfd f0, 40(r3)
        lfd f1, 32(r3)
        lfd f0, 24(r3)
        lfd f0, 16(r3)
        lfd f0, 8(r3)
        lfd f0, 0(r3)
        blr

llvm-svn: 27296
2006-03-31 18:06:18 +00:00
Chris Lattner
20e619fba3 When building a VVECTOR_SHUFFLE node from extract_element operations, make
sure to build it as SHUFFLE(X, undef, mask), not SHUFFLE(X, X, mask).

The later is not canonical form, and prevents the PPC splat pattern from
matching.  For a particular splat, we go from generating this:

	li r10, lo16(LCPI1_0)
	lis r11, ha16(LCPI1_0)
	lvx v3, r11, r10
	vperm v3, v2, v2, v3

to generating:

	vspltw v3, v2, 3

llvm-svn: 27236
2006-03-28 22:19:47 +00:00
Chris Lattner
a46dfe80c8 Canonicalize VECTOR_SHUFFLE(X, X, Y) -> VECTOR_SHUFFLE(X,undef,Y')
llvm-svn: 27235
2006-03-28 22:11:53 +00:00
Chris Lattner
c9992548fc Turn a series of extract_element's feeding a build_vector into a
vector_shuffle node.  For this:

void test(__m128 *res, __m128 *A, __m128 *B) {
  *res = _mm_unpacklo_ps(*A, *B);
}

we now produce this code:

_test:
        movl 8(%esp), %eax
        movaps (%eax), %xmm0
        movl 12(%esp), %eax
        unpcklps (%eax), %xmm0
        movl 4(%esp), %eax
        movaps %xmm0, (%eax)
        ret

instead of this:

_test:
        subl $76, %esp
        movl 88(%esp), %eax
        movaps (%eax), %xmm0
        movaps %xmm0, (%esp)
        movaps %xmm0, 32(%esp)
        movss 4(%esp), %xmm0
        movss 32(%esp), %xmm1
        unpcklps %xmm0, %xmm1
        movl 84(%esp), %eax
        movaps (%eax), %xmm0
        movaps %xmm0, 16(%esp)
        movaps %xmm0, 48(%esp)
        movss 20(%esp), %xmm0
        movss 48(%esp), %xmm2
        unpcklps %xmm0, %xmm2
        unpcklps %xmm1, %xmm2
        movl 80(%esp), %eax
        movaps %xmm2, (%eax)
        addl $76, %esp
        ret

GCC produces this (with -fomit-frame-pointer):

_test:
        subl    $12, %esp
        movl    20(%esp), %eax
        movaps  (%eax), %xmm0
        movl    24(%esp), %eax
        unpcklps        (%eax), %xmm0
        movl    16(%esp), %eax
        movaps  %xmm0, (%eax)
        addl    $12, %esp
        ret

llvm-svn: 27233
2006-03-28 20:28:38 +00:00
Chris Lattner
b7163598f9 Don't crash on X^X if X is a vector. Instead, produce a vector of zeros.
llvm-svn: 27229
2006-03-28 19:11:05 +00:00
Chris Lattner
dc1eab5886 Don't call SimplifyDemandedBits on vectors
llvm-svn: 27128
2006-03-25 22:19:00 +00:00
Chris Lattner
5336a59e4b fold insertelement(buildvector) -> buildvector if the inserted element # is
a constant.  This implements test_constant_insert in CodeGen/Generic/vector.ll

llvm-svn: 26851
2006-03-19 01:27:56 +00:00
Nate Begeman
bb01d4f272 Remove BRTWOWAY*
Make the PPC backend not dependent on BRTWOWAY_CC and make the branch
selector smarter about the code it generates, fixing a case in the
readme.

llvm-svn: 26814
2006-03-17 01:40:33 +00:00
Chris Lattner
68ac09d5cb make sure dead token factor nodes are removed by the dag combiner.
llvm-svn: 26731
2006-03-13 18:37:30 +00:00
Chris Lattner
d8c2a48d58 Fold X+Y -> X|Y when safe. This implements:
Regression/CodeGen/PowerPC/and_add.ll

a case that occurs with dynamic allocas of constant size.

llvm-svn: 26727
2006-03-13 06:51:27 +00:00
Chris Lattner
8bb6cb7d7b add a couple of missing folds
llvm-svn: 26724
2006-03-13 06:26:26 +00:00
Chris Lattner
bdaf4f38b5 Reinstate this now that the offending opposite xform has been removed.
llvm-svn: 26548
2006-03-05 19:53:55 +00:00
Evan Cheng
d428e22c07 Back out fold (shl (add x, c1), c2) -> (add (shl x, c2), c1<<c2) for now.
It's causing an infinite loop compiling ldecod on x86 / Darwin.

llvm-svn: 26544
2006-03-05 07:30:16 +00:00
Chris Lattner
3bc4050217 Add some simple copysign folds
llvm-svn: 26543
2006-03-05 05:30:57 +00:00
Chris Lattner
f29f5204cc fold (mul (add x, c1), c2) -> (add (mul x, c2), c1*c2)
fold (shl (add x, c1), c2) -> (add (shl x, c2), c1<<c2)

This allows us to compile CodeGen/PowerPC/addi-reassoc.ll into:

_test1:
        slwi r2, r4, 4
        add r2, r2, r3
        lwz r3, 36(r2)
        blr
_test2:
        mulli r2, r4, 5
        add r2, r2, r3
        lbz r2, 11(r2)
        extsb r3, r2
        blr

instead of:

_test1:
        addi r2, r4, 2
        slwi r2, r2, 4
        add r2, r3, r2
        lwz r3, 4(r2)
        blr
_test2:
        addi r2, r4, 2
        mulli r2, r2, 5
        add r2, r3, r2
        lbz r2, 1(r2)
        extsb r3, r2
        blr

llvm-svn: 26535
2006-03-04 23:33:26 +00:00
Chris Lattner
0db2f2c689 Fix CodeGen/Generic/2006-03-01-dagcombineinfloop.ll, an infinite loop
in the dag combiner on 176.gcc on x86.

llvm-svn: 26459
2006-03-01 21:47:21 +00:00
Chris Lattner
232024edb8 Fix a typo evan noticed
llvm-svn: 26454
2006-03-01 19:55:35 +00:00
Chris Lattner
bc1c85beea Add support for target-specific dag combines
llvm-svn: 26443
2006-03-01 04:53:38 +00:00
Chris Lattner
fbcd62d3bb Add a new AddToWorkList method, start using it
llvm-svn: 26441
2006-03-01 04:03:14 +00:00
Chris Lattner
324871ef1a Pull shifts by a constant through multiplies (a form of reassociation),
implementing Regression/CodeGen/X86/mul-shift-reassoc.ll

llvm-svn: 26440
2006-03-01 03:44:24 +00:00
Evan Cheng
b97aab4371 Vector ops lowering.
llvm-svn: 26436
2006-03-01 01:09:54 +00:00
Chris Lattner
f0032b350c Compile:
unsigned foo4(unsigned short *P) { return *P & 255; }
unsigned foo5(short *P) { return *P & 255; }

to:

_foo4:
        lbz r3,1(r3)
        blr
_foo5:
        lbz r3,1(r3)
        blr

not:

_foo4:
        lhz r2, 0(r3)
        rlwinm r3, r2, 0, 24, 31
        blr
_foo5:
        lhz r2, 0(r3)
        rlwinm r3, r2, 0, 24, 31
        blr

llvm-svn: 26419
2006-02-28 06:49:37 +00:00
Chris Lattner
bdbc4476d9 Fold "and (LOAD P), 255" -> zextload. This allows us to compile:
unsigned foo3(unsigned *P) { return *P & 255; }
as:
_foo3:
        lbz r3, 3(r3)
        blr

instead of:

_foo3:
        lwz r2, 0(r3)
        rlwinm r3, r2, 0, 24, 31
        blr

and:

unsigned short foo2(float a) { return a; }

as:
_foo2:
        fctiwz f0, f1
        stfd f0, -8(r1)
        lhz r3, -2(r1)
        blr

instead of:

_foo2:
        fctiwz f0, f1
        stfd f0, -8(r1)
        lwz r2, -4(r1)
        rlwinm r3, r2, 0, 16, 31
        blr

llvm-svn: 26417
2006-02-28 06:35:35 +00:00
Chris Lattner
0f8a727c49 fold (sra (sra x, c1), c2) -> (sra x, c1+c2)
llvm-svn: 26416
2006-02-28 06:23:04 +00:00
Chris Lattner
47ee42829d remove some completed notes
llvm-svn: 26390
2006-02-27 00:39:31 +00:00
Chris Lattner
301f45cf6f Fix a problem Nate and Duraid reported where simplifying nodes can cause
them to get ressurected, in which case, deleting the undead nodes is
unfriendly.

llvm-svn: 26291
2006-02-20 06:51:04 +00:00
Nate Begeman
abac61603f Add checks to make sure we don't create bogus extend nodes, and fix a bug
where we were doing exactly that which was causing failures on x86 and
alpha.

llvm-svn: 26284
2006-02-18 02:40:58 +00:00
Chris Lattner
375e1a71cc Fix a tricky issue in the SimplifyDemandedBits code where CombineTo wasn't
exactly the API we wanted to call into.  This fixes the crash on crafty last
night.

llvm-svn: 26269
2006-02-17 21:58:01 +00:00
Nate Begeman
fb5dbadf15 Clean up DemandedBitsAreZero interface
Make more use of the new mask helpers in valuetypes.h
Combine (sra (srl x, c1), c1) -> sext_inreg if legal

llvm-svn: 26263
2006-02-17 19:54:08 +00:00
Nate Begeman
57b3567552 Don't expand sdiv by power of two before legalize, since it will likely
generate illegal nodes.

llvm-svn: 26261
2006-02-17 07:26:20 +00:00
Nate Begeman
5965bd19f8 kill ADD_PARTS & SUB_PARTS and replace them with fancy new ADDC, ADDE, SUBC
and SUBE nodes that actually expose what's going on and allow for
significant simplifications in the targets.

llvm-svn: 26255
2006-02-17 05:43:56 +00:00
Nate Begeman
8a77efe4f7 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.

llvm-svn: 26238
2006-02-16 21:11:51 +00:00
Chris Lattner
471627c49d Lowering of sdiv X, pow2 was broken, this fixes it. This patch is written
by Nate, I'm just committing it for him.

llvm-svn: 26230
2006-02-16 08:02:36 +00:00
Jim Laskey
2eea436192 Should not combine ISD::LOCATIONs until we have scheme to remove from
MachineDebugInfo tables.

llvm-svn: 26216
2006-02-15 19:34:44 +00:00
Chris Lattner
a10e23c19f Compile this:
xori r6, r2, 1
        rlwinm r6, r6, 0, 31, 31
        cmpwi cr0, r6, 0
        bne cr0, LBB1_3 ; endif

to this:

        rlwinm r6, r2, 0, 31, 31
        cmpwi cr0, r6, 0
        beq cr0, LBB1_3 ; endif

llvm-svn: 26047
2006-02-08 02:13:15 +00:00
Nate Begeman
8c9cd461df Back out previous commit, it isn't safe.
llvm-svn: 26006
2006-02-05 08:23:00 +00:00
Nate Begeman
3dc8b89493 fold c1 << (x + c2) into (c1 << c2) << x. fix a warning.
llvm-svn: 26005
2006-02-05 08:07:24 +00:00
Nate Begeman
c89fdf1eb3 Handle urem by shifted powers of 2.
llvm-svn: 26001
2006-02-05 07:36:48 +00:00
Nate Begeman
25d178bece handle combining A / (B << N) into A >>u (log2(B)+N) when B is a power of 2
llvm-svn: 26000
2006-02-05 07:20:23 +00:00
Nate Begeman
dc7bba9ffe Add a framework for eliminating instructions that produces undemanded bits.
llvm-svn: 25945
2006-02-03 22:24:05 +00:00
Nate Begeman
22e251abf1 Add common code for reassociating ops in the dag combiner
llvm-svn: 25934
2006-02-03 06:46:56 +00:00
Chris Lattner
49beaf40fc Turn any_extend nodes into zero_extend nodes when it allows us to remove an
and instruction.  This allows us to compile stuff like this:

bool %X(int %X) {
        %Y = add int %X, 14
        %Z = setne int %Y, 12345
        ret bool %Z
}

to this:

_X:
        cmpl $12331, 4(%esp)
        setne %al
        movzbl %al, %eax
        ret

instead of this:

_X:
        cmpl $12331, 4(%esp)
        setne %al
        movzbl %al, %eax
        andl $1, %eax
        ret

This occurs quite a bit with the X86 backend.  For example, 25 times in
lambda, 30 times in 177.mesa, 14 times in galgel,  70 times in fma3d,
25 times in vpr, several hundred times in gcc, ~45 times in crafty,
~60 times in parser, ~140 times in eon, 110 times in perlbmk, 55 on gap,
16 times on bzip2, 14 times on twolf, and 1-2 times in many other SPEC2K
programs.

llvm-svn: 25901
2006-02-02 07:17:31 +00:00
Chris Lattner
49ce35542f add two dag combines:
(C1-X) == C2 --> X == C1-C2
(X+C1) == C2 --> X == C2-C1

This allows us to compile this:

bool %X(int %X) {
        %Y = add int %X, 14
        %Z = setne int %Y, 12345
        ret bool %Z
}

into this:

_X:
        cmpl $12331, 4(%esp)
        setne %al
        movzbl %al, %eax
        andl $1, %eax
        ret

not this:

_X:
        movl $14, %eax
        addl 4(%esp), %eax
        cmpl $12345, %eax
        setne %al
        movzbl %al, %eax
        andl $1, %eax
        ret

Testcase here: Regression/CodeGen/X86/compare-add.ll

nukage of the and coming up next.

llvm-svn: 25898
2006-02-02 06:36:13 +00:00
Nate Begeman
7e7f439f85 Fix some of the stuff in the PPC README file, and clean up legalization
of the SELECT_CC, BR_CC, and BRTWOWAY_CC nodes.

llvm-svn: 25875
2006-02-01 07:19:44 +00:00
Chris Lattner
f0b24d2dc0 Move MaskedValueIsZero from the DAGCombiner to the TargetLowering interface,making isMaskedValueZeroForTargetNode simpler, and useable from other partsof the compiler.
llvm-svn: 25803
2006-01-30 04:09:27 +00:00
Chris Lattner
3b40e64aa3 pass the address of MaskedValueIsZero into isMaskedValueZeroForTargetNode,
to permit recursion

llvm-svn: 25799
2006-01-30 03:49:37 +00:00
Chris Lattner
678da98835 eliminate uses of SelectionDAG::getBR2Way_CC
llvm-svn: 25767
2006-01-29 06:00:45 +00:00
Nate Begeman
af397cec0b Add a missing case to the dag combiner.
llvm-svn: 25723
2006-01-28 01:06:30 +00:00
Chris Lattner
de02d7727f Add explicit #includes of <iostream>
llvm-svn: 25515
2006-01-22 23:41:00 +00:00
Nate Begeman
569c439567 Get rid of code in the DAGCombiner that is duplicated in SelectionDAG.cpp
Now all constant folding in the code generator is in one place.

llvm-svn: 25426
2006-01-18 22:35:16 +00:00
Chris Lattner
5fee908be5 Fix a backwards conditional that caused an inf loop in some cases. This
fixes: test/Regression/CodeGen/Generic/2005-01-18-SetUO-InfLoop.ll

llvm-svn: 25419
2006-01-18 19:13:41 +00:00
Chris Lattner
fcdb420baf Disable two transformations that contribute to bus errors on SparcV8.
llvm-svn: 25339
2006-01-15 18:58:59 +00:00
Chris Lattner
3470b5dee6 Add a simple missing fold to produce this:
subfic r3, r2, 33

instead of this:

        subfic r2, r2, 32
        addi r3, r2, 1

llvm-svn: 25255
2006-01-12 20:22:43 +00:00
Chris Lattner
b1ee616de9 Don't create rotate instructions in unsupported types, because we don't have
promote/expand code yet.  This fixes the 177.mesa failure on PPC.

llvm-svn: 25250
2006-01-12 18:57:33 +00:00
Nate Begeman
1b8121b227 Add bswap, rotl, and rotr nodes
Add dag combiner code to recognize rotl, rotr
Add ppc code to match rotl

Targets should add rotl/rotr patterns if they have them

llvm-svn: 25222
2006-01-11 21:21:00 +00:00
Evan Cheng
85c973cda9 Revert the previous check-in. Leave shl x, 1 along for target to deal with.
llvm-svn: 25121
2006-01-06 01:56:02 +00:00
Evan Cheng
b03f9b32d2 fold (shl x, 1) -> (add x, x)
llvm-svn: 25120
2006-01-06 01:06:31 +00:00
Jim Laskey
762e9ec06c Added initial support for DEBUG_LABEL allowing debug specific labels to be
inserted in the code.

llvm-svn: 25104
2006-01-05 01:25:28 +00:00
Jim Laskey
0da76a676a Add unique id to debug location for debug label use (work in progress.)
llvm-svn: 25096
2006-01-04 15:04:11 +00:00
Jim Laskey
bdba3e2a46 Remove redundant debug locations.
llvm-svn: 24995
2005-12-23 20:08:28 +00:00
Chris Lattner
26943b9691 Simplify store(bitconv(x)) to store(x). This allows us to compile this:
void bar(double Y, double *X) {
  *X = Y;
}

to this:

bar:
        save -96, %o6, %o6
        st %i1, [%i2+4]
        st %i0, [%i2]
        restore %g0, %g0, %g0
        retl
        nop

instead of this:

bar:
        save -104, %o6, %o6
        st %i1, [%i6+-4]
        st %i0, [%i6+-8]
        ldd [%i6+-8], %f0
        std  %f0, [%i2]
        restore %g0, %g0, %g0
        retl
        nop

on sparcv8.

llvm-svn: 24983
2005-12-23 05:48:07 +00:00
Chris Lattner
54560f6887 fold (conv (load x)) -> (load (conv*)x).
This allows us to compile this:
void foo(double);
void bar(double *X) { foo(*X); }

To this:

bar:
        save -96, %o6, %o6
        ld [%i0+4], %o1
        ld [%i0], %o0
        call foo
        nop
        restore %g0, %g0, %g0
        retl
        nop

instead of this:

bar:
        save -104, %o6, %o6
        ldd [%i0], %f0
        std %f0, [%i6+-8]
        ld [%i6+-4], %o1
        ld [%i6+-8], %o0
        call foo
        nop
        restore %g0, %g0, %g0
        retl
        nop

on SparcV8.

llvm-svn: 24982
2005-12-23 05:44:41 +00:00
Chris Lattner
efbbedbf4a Fold bitconv(bitconv(x)) -> x. We now compile this:
void foo(double);
void bar(double X) { foo(X); }

to this:

bar:
        save -96, %o6, %o6
        or %g0, %i0, %o0
        or %g0, %i1, %o1
        call foo
        nop
        restore %g0, %g0, %g0
        retl
        nop

instead of this:

bar:
        save -112, %o6, %o6
        st %i1, [%i6+-4]
        st %i0, [%i6+-8]
        ldd [%i6+-8], %f0
        std %f0, [%i6+-16]
        ld [%i6+-12], %o1
        ld [%i6+-16], %o0
        call foo
        nop
        restore %g0, %g0, %g0
        retl
        nop

on V8.

llvm-svn: 24981
2005-12-23 05:37:50 +00:00
Chris Lattner
a187460552 constant fold bits_convert in getNode and in the dag combiner for fp<->int
conversions.  This allows V8 to compiles this:

void %test() {
        call float %test2( float 1.000000e+00, float 2.000000e+00, double 3.000000e+00, double* null )
        ret void
}

into:

test:
        save -96, %o6, %o6
        sethi 0, %o3
        sethi 1049088, %o2
        sethi 1048576, %o1
        sethi 1040384, %o0
        or %g0, %o3, %o4
        call test2
        nop
        restore %g0, %g0, %g0
        retl
        nop

instead of:

test:
        save -112, %o6, %o6
        sethi 0, %o4
        sethi 1049088, %l0
        st %o4, [%i6+-12]
        st %l0, [%i6+-16]
        ld [%i6+-12], %o3
        ld [%i6+-16], %o2
        sethi 1048576, %o1
        sethi 1040384, %o0
        call test2
        nop
        restore %g0, %g0, %g0
        retl
        nop

llvm-svn: 24980
2005-12-23 05:30:37 +00:00
Evan Cheng
9cdc16c6d3 * Fix a GlobalAddress lowering bug.
* Teach DAG combiner about X86ISD::SETCC by adding a TargetLowering hook.

llvm-svn: 24921
2005-12-21 23:05:39 +00:00
Chris Lattner
83e4407379 Don't create SEXTLOAD/ZEXTLOAD instructions that the target doesn't support
if after legalize.  This fixes IA64 failures.

llvm-svn: 24725
2005-12-15 19:02:38 +00:00
Chris Lattner
d39c60fcc8 When folding loads into ops, immediately replace uses of the op with the
load.  This reduces number of worklist iterations and avoid missing optimizations
depending on folding of things into sext_inreg nodes (which aren't supported by
all targets).
Tested by Regression/CodeGen/X86/extend.ll:test2

llvm-svn: 24712
2005-12-14 19:25:30 +00:00
Chris Lattner
7dac1083da Fix the (zext (zextload)) case to trigger, similarly for sign extends.
Allow (zext (truncate)) to apply after legalize if the target supports
AND (which all do).

This compiles
short %foo() {
        %tmp.0 = load ubyte* %X         ; <ubyte> [#uses=1]
        %tmp.3 = cast ubyte %tmp.0 to short             ; <short> [#uses=1]
        ret short %tmp.3
}

to:
_foo:
        movzbl _X, %eax
        ret

instead of:

_foo:
        movzbl _X, %eax
        movzbl %al, %eax
        ret

thanks to Evan for pointing this out.

llvm-svn: 24709
2005-12-14 19:05:06 +00:00
Chris Lattner
f753d1a574 Fix a miscompilation in crafty due to a recent patch
llvm-svn: 24706
2005-12-14 07:58:38 +00:00
Evan Cheng
bce7c47306 Fold (zext (load x) to (zextload x).
llvm-svn: 24702
2005-12-14 02:19:23 +00:00
Chris Lattner
57c882edf8 Only transform (sext (truncate x)) -> (sextinreg x) if before legalize or
if the target supports the resultant sextinreg

llvm-svn: 24632
2005-12-07 18:02:05 +00:00
Chris Lattner
cbd3d01a43 Teach the dag combiner to turn a truncate/sign_extend pair into a sextinreg
when the types match up.  This allows the X86 backend to compile:

sbyte %toggle_value(sbyte* %tmp.1) {
        %tmp.2 = load sbyte* %tmp.1
        ret sbyte %tmp.2
}

to this:

_toggle_value:
        mov %EAX, DWORD PTR [%ESP + 4]
        movsx %EAX, BYTE PTR [%EAX]
        ret

instead of this:

_toggle_value:
        mov %EAX, DWORD PTR [%ESP + 4]
        movsx %EAX, BYTE PTR [%EAX]
        movsx %EAX, %AL
        ret

noticed in Shootout/objinst.

-Chris

llvm-svn: 24630
2005-12-07 07:11:03 +00:00
Jeff Cohen
cf1f782a2f Fix operator precedence bug caught by VC++.
llvm-svn: 24318
2005-11-12 00:59:01 +00:00
Chris Lattner
bf4f233214 Switch the allnodes list from a vector of pointers to an ilist of nodes.This eliminates the vector, allows constant time removal of a node froma graph, and makes iteration over the all nodes list stable when adding
nodes to the graph.

llvm-svn: 24263
2005-11-09 23:47:37 +00:00
Nate Begeman
ee065281e8 Fix a crash that Andrew noticed, and add a pair of braces to unfconfuse
XCode's indenting.

llvm-svn: 24159
2005-11-02 18:42:59 +00:00
Chris Lattner
17df608719 Fix a source of undefined behavior when dealing with 64-bit types. This
may fix PR652.  Thanks to Andrew for tracking down the problem.

llvm-svn: 24145
2005-11-02 01:47:04 +00:00
Chris Lattner
a70878d4fb Codegen mul by negative power of two with a shift and negate.
This implements test/Regression/CodeGen/PowerPC/mul-neg-power-2.ll,
producing:

_foo:
        slwi r2, r3, 1
        subfic r3, r2, 63
        blr

instead of:

_foo:
        mulli r2, r3, -2
        addi r3, r2, 63
        blr

llvm-svn: 24106
2005-10-30 06:41:49 +00:00
Chris Lattner
4b6d583d7a Fix DSE to not nuke dead stores unless they redundant store is the same
VT as the killing one.  Fix fixes PR491

llvm-svn: 24034
2005-10-27 07:10:34 +00:00
Chris Lattner
d8c5c066a1 Add a simple xform that is useful for bitfield operations.
llvm-svn: 24029
2005-10-27 05:06:38 +00:00
Chris Lattner
3b409a85eb Clear a bit in this file that was causing a miscompilation of 178.galgel.
llvm-svn: 23980
2005-10-25 18:57:30 +00:00
Chris Lattner
9faa5b7a9a BuildSDIV and BuildUDIV only work for i32/i64, but they don't check that
the input is that type, this caused a failure on gs on X86 last night.
Move the hard checks into Build[US]Div since that is where decisions like
this should be made.

llvm-svn: 23881
2005-10-22 18:50:15 +00:00
Chris Lattner
75ea5b10bf add a case missing from the dag combiner that exposed the failure on
2005-10-21-longlonggtu.ll.

llvm-svn: 23875
2005-10-21 21:23:25 +00:00
Nate Begeman
8f62cd32ad Fix a typo in the dag combiner, so that this can work on i64 targets
llvm-svn: 23856
2005-10-21 01:51:45 +00:00
Nate Begeman
4dd383120f Invert the TargetLowering flag that controls divide by consant expansion.
Add a new flag to TargetLowering indicating if the target has really cheap
  signed division by powers of two, make ppc use it.  This will probably go
  away in the future.
Implement some more ISD::SDIV folds in the dag combiner
Remove now dead code in the x86 backend.

llvm-svn: 23853
2005-10-21 00:02:42 +00:00
Nate Begeman
7efe53d90b Fix a couple bugs in the const div stuff where we'd generate MULHS/MULHU
for types that aren't legal, and fail a divisor is less than zero
comparison, which would cause us to drop a subtract.

llvm-svn: 23846
2005-10-20 17:45:03 +00:00
Chris Lattner
a6efeb01f9 don't use llabs with apparently VC++ doesn't have
llvm-svn: 23845
2005-10-20 17:01:00 +00:00
Nate Begeman
c6f067a8c4 Move the target constant divide optimization up into the dag combiner, so
that the nodes can be folded with other nodes, and we can not duplicate
code in every backend.  Alpha will probably want this too.

llvm-svn: 23835
2005-10-20 02:15:44 +00:00
Chris Lattner
6c14c35bd7 Fold (select C, load A, load B) -> load (select C, A, B). This happens quite
a lot throughout many programs.  In particular, specfp triggers it a bunch for
constant FP nodes when you have code like  cond ? 1.0 : -1.0.

If the PPC ISel exposed the loads implicit in pic references to external globals,
we would be able to eliminate a load in cases like this as well:

%X = external global int
%Y = external global int
int* %test4(bool %C) {
        %G = select bool %C, int* %X, int* %Y
        ret int* %G
}

Note that this breaks things that use SrcValue's (see the fixme), but since nothing
uses them yet, this is ok.

Also, simplify some code to use hasOneUse() on an SDOperand instead of hasNUsesOfValue directly.

llvm-svn: 23781
2005-10-18 06:04:22 +00:00
Nate Begeman
418c6e4045 Implement some feedback from Chris re: constant canonicalization
llvm-svn: 23777
2005-10-18 00:28:13 +00:00
Nate Begeman
ec48a1bfbd fold fmul X, +2.0 -> fadd X, X;
llvm-svn: 23774
2005-10-17 20:40:11 +00:00
Chris Lattner
eeb2bda2fa add a trivial fold
llvm-svn: 23764
2005-10-17 01:07:11 +00:00
Chris Lattner
e540800d5a Fix this logic.
llvm-svn: 23756
2005-10-15 22:35:40 +00:00
Chris Lattner
17cc9edd33 Add a case we were missing that was causing us to fail CodeGen/PowerPC/rlwinm.ll:test3
llvm-svn: 23755
2005-10-15 22:18:08 +00:00
Nate Begeman
6e673b24d3 fold sext_in_reg, sext_in_reg where both have the same VT. This was
popping up in Fourinarow.

llvm-svn: 23722
2005-10-14 01:29:07 +00:00
Nate Begeman
d59e5a7abb Relax the checking on zextload generation a bit, since as sabre pointed out
you could be AND'ing with the result of a shift that shifts out all the
bits you care about, in addition to a constant.

Also, move over an add/sub_parts fold from legalize to the dag combiner,
where it works for things other than constants.  Woot!

llvm-svn: 23720
2005-10-14 01:12:21 +00:00
Chris Lattner
b8282987f4 Fix the trunc(load) case, finally allowing crafty and povray to pass
llvm-svn: 23718
2005-10-13 22:10:05 +00:00
Chris Lattner
dbc5ae3109 Fix some bugs in (sext (load x))
llvm-svn: 23717
2005-10-13 21:52:31 +00:00
Nate Begeman
8e022b3d89 Fix the remaining DAGCombiner issues pointed out by sabre. This should fix
the remainder of the failures introduced by my patch last night.

llvm-svn: 23714
2005-10-13 18:34:58 +00:00
Chris Lattner
a80f1f6e72 Fix a minor bug in the dag combiner that broke pcompress2 and some other
tests.

llvm-svn: 23713
2005-10-13 18:16:34 +00:00
Nate Begeman
02b23c6065 Move some Legalize functionality over to the DAGCombiner where it belongs.
Kill some dead code.

llvm-svn: 23706
2005-10-13 03:11:28 +00:00
Nate Begeman
70d28c5e32 Fix a potential bug with two combine-to's back to back that chris pointed
out, where after the first CombineTo() call, the node the second CombineTo
wishes to replace may no longer exist.

Fix a very real bug with the truncated load optimization on little endian
targets, which do not need a byte offset added to the load.

llvm-svn: 23704
2005-10-12 23:18:53 +00:00
Nate Begeman
8caf81d617 More cool stuff for the dag combiner. We can now finally handle things
like turning:

_foo:
        fctiwz f0, f1
        stfd f0, -8(r1)
        lwz r2, -4(r1)
        rlwinm r3, r2, 0, 16, 31
        blr

into
_foo:
        fctiwz f0,f1
        stfd f0,-8(r1)
        lhz r3,-2(r1)
        blr

Also removed an unncessary constraint from sra -> srl conversion, which
should take care of hte only reason we would ever need to handle sra in
MaskedValueIsZero, AFAIK.

llvm-svn: 23703
2005-10-12 20:40:40 +00:00
Chris Lattner
514f058be1 Fix a powerpc crash on CodeGen/Generic/llvm-ct-intrinsics.ll
llvm-svn: 23694
2005-10-11 17:56:34 +00:00
Chris Lattner
c38fb8e2a1 Add a canonicalization that got lost, fixing PowerPC/fold-li.ll:SUB
llvm-svn: 23693
2005-10-11 06:07:15 +00:00
Chris Lattner
cc6e53e6ee clean up some corner cases
llvm-svn: 23692
2005-10-10 23:00:08 +00:00
Chris Lattner
04c737091f Implement trivial DSE. If two stores are neighbors and store to the same
location, replace them with a new store of the last value.  This occurs
in the same neighborhood in 197.parser, speeding it up about 1.5%

llvm-svn: 23691
2005-10-10 22:31:19 +00:00
Chris Lattner
e260ed8628 Add support for CombineTo, allowing the dag combiner to replace nodes with
multiple results.

Use this support to implement trivial store->load forwarding, implementing
CodeGen/PowerPC/store-load-fwd.ll.  Though this is the most simple case and
can be extended in the future, it is still useful.  For example, it speeds
up 197.parser by 6.2% by avoiding an LSU reject in xalloc:

        stw r6, lo16(l5_end_of_array)(r2)
        addi r2, r5, -4
        stwx r5, r4, r2
-       lwzx r5, r4, r2
-       rlwinm r5, r5, 0, 0, 30
        stwx r5, r4, r2
        lwz r2, -4(r4)
        ori r2, r2, 1

llvm-svn: 23690
2005-10-10 22:04:48 +00:00
Nate Begeman
6828ed9bfd Teach the DAGCombiner several new tricks, teaching it how to turn
sext_inreg into zext_inreg based on the signbit (fires a lot), srem into
urem, etc.

llvm-svn: 23688
2005-10-10 21:26:48 +00:00
Chris Lattner
7730924067 Fix comment
llvm-svn: 23686
2005-10-10 16:52:03 +00:00
Chris Lattner
3d1d4a3d12 Add ISD::ADD to MaskedValueIsZero
llvm-svn: 23685
2005-10-10 16:51:40 +00:00
Chris Lattner
6a49b7cabb add a todo for something I noticed
llvm-svn: 23679
2005-10-09 22:59:08 +00:00
Chris Lattner
1d3dc00674 (X & Y) & C == 0 if either X&C or Y&C are zero
llvm-svn: 23678
2005-10-09 22:12:36 +00:00
Nate Begeman
2042aa5b92 Lo and behold, the last bits of SelectionDAG.cpp have been moved over.
llvm-svn: 23665
2005-10-08 00:29:44 +00:00
Chris Lattner
fb12624a3f implement CodeGen/PowerPC/div-2.ll:test2-4 by propagating zero bits through
C-X's

llvm-svn: 23662
2005-10-07 15:30:32 +00:00
Chris Lattner
5bcd0dd811 Turn sdivs into udivs when we can prove the sign bits are clear. This
implements CodeGen/PowerPC/div-2.ll

llvm-svn: 23659
2005-10-07 06:10:46 +00:00
Nate Begeman
bd7df030d2 Check in some more DAGCombiner pieces
llvm-svn: 23639
2005-10-05 21:43:42 +00:00
Chris Lattner
a49e16fefa implement visitBR_CC so that PowerPC/inverted-bool-compares.ll passes
with the dag combiner.  This speeds up espresso by 8%, reaching performance
parity with the dag-combiner-disabled llc.

llvm-svn: 23636
2005-10-05 06:47:48 +00:00
Chris Lattner
06f1d0f73a Add a new HandleNode class, which is used to handle (haha) cases in the
dead node elim and dag combiner passes where the root is potentially updated.
This fixes a fixme in the dag combiner.

llvm-svn: 23634
2005-10-05 06:35:28 +00:00
Chris Lattner
a6895d180e Implement the code for PowerPC/inverted-bool-compares.ll, even though it
that testcase still does not pass with the dag combiner.  This is because
not all forms of br* are folded yet.

Also, when we combine a node into another one, delete the node immediately
instead of waiting for the node to potentially come up in the future.

llvm-svn: 23632
2005-10-05 06:11:08 +00:00
Chris Lattner
746d50a01a Fix a crash compiling Olden/tsp
llvm-svn: 23630
2005-10-05 04:45:43 +00:00
Chris Lattner
6f3b577ee6 Add FP versions of the binary operators, keeping the int and fp worlds seperate.
Though I have done extensive testing, it is possible that this will break
things in configs I can't test.  Please let me know if this causes a problem
and I'll fix it ASAP.

llvm-svn: 23504
2005-09-28 22:28:18 +00:00
Nate Begeman
c760f80fed Stub out the rest of the DAG Combiner. Just need to fill in the
select_cc bits and then wrap it in a convenience function for  use with
regular select.

llvm-svn: 23389
2005-09-19 22:34:01 +00:00
Nate Begeman
24a7eca282 More DAG combining. Still need the branch instructions, and select_cc
llvm-svn: 23371
2005-09-16 00:54:12 +00:00
Chris Lattner
bd39c1a4c6 Add a missing #include, patch courtesy of Baptiste Lepilleur.
llvm-svn: 23302
2005-09-09 23:53:39 +00:00
Nate Begeman
049b748c76 Last round of 2-node folds from SD.cpp. Will move on to 3 node ops such
as setcc and select next.

llvm-svn: 23295
2005-09-09 19:49:52 +00:00
Nate Begeman
85c1cc4523 Move yet more folds over to the dag combiner from sd.cpp
llvm-svn: 23278
2005-09-08 20:18:10 +00:00
Nate Begeman
2cc2c9a79c Another round of dag combiner changes. This fixes some missing XOR folds
as well as fixing how we replace old values with new values.

llvm-svn: 23260
2005-09-07 23:25:52 +00:00
Nate Begeman
6791d63e55 Implement a common missing fold, (add (add x, c1), c2) -> (add x, c1+c2).
This restores all of stanford to being identical with and without the dag
combiner with the add folding turned off in sd.cpp.

llvm-svn: 23258
2005-09-07 16:09:19 +00:00
Nate Begeman
007c650699 Add an option to the DAG Combiner to enable it for beta runs, and turn on
that option for PowerPC's beta.

llvm-svn: 23253
2005-09-07 00:15:36 +00:00
Nate Begeman
d23739d020 Next round of DAGCombiner changes. This version now passes all the tests
I have run so far when run before Legalize.  It still needs to pick up the
SetCC folds, and nodes that use SetCC.

llvm-svn: 23243
2005-09-06 04:43:02 +00:00
Nate Begeman
7cea6ef16e Next round of DAG Combiner changes. Just need to support multiple return
values, and then we should be able to hook it up.

llvm-svn: 23231
2005-09-02 21:18:40 +00:00
Nate Begeman
2504fe2613 Implement first round of feedback from chris (there's still a couple things
left to do).

llvm-svn: 23195
2005-09-01 23:24:04 +00:00
Nate Begeman
e8f78d1aab Add the rest of the currently implemented visit routines to the switch
statement in visit().

llvm-svn: 23185
2005-09-01 00:33:32 +00:00
Nate Begeman
21158fc485 First pass at the DAG Combiner. It isn't used anywhere yet, but it should
be mostly functional.  It currently has all folds from SelectionDAG.cpp
that do not involve a condition code.

llvm-svn: 23184
2005-09-01 00:19:25 +00:00