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178 Commits

Author SHA1 Message Date
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