Commit Graph

323 Commits

Author SHA1 Message Date
Dan Gohman 80f9f077e3 Don't call SimplifyVBinOp for non-vector operations, following earlier review
feedback. This theoretically makes the common (scalar) case more efficient.

llvm-svn: 39823
2007-07-13 20:03:40 +00:00
Dan Gohman adb3d37c07 Fix a bug in the folding of binary operators to undef.
Thanks to Lauro for spotting this!

llvm-svn: 38491
2007-07-10 15:19:29 +00:00
Dan Gohman fa91282dbf Fix the folding of undef in several binary operators to recognize
undef in either the left or right operand.

llvm-svn: 38489
2007-07-10 14:20:37 +00:00
Dan Gohman 2af3063337 Preserve volatililty and alignment information when lowering or
simplifying loads and stores.

llvm-svn: 38473
2007-07-09 22:18:38 +00:00
Chris Lattner 6caf8fdd04 Fix this warning:
DAGCombiner.cpp: In member function 'llvm::SDOperand<unnamed>::DAGCombiner::visitOR(llvm::SDNode*)':
DAGCombiner.cpp:1608: warning: passing negative value '-0x00000000000000001' for argument 1 to 'llvm::SDOperand llvm::SelectionDAG::getConstant(uint64_t, llvm::MVT::ValueType, bool)'

oiy.

llvm-svn: 38458
2007-07-09 16:16:34 +00:00
Dan Gohman 06563a8702 Fix several over-aggressive folds for undef nodes in dagcombine, to
follow the rules for undef used in instcombine.

llvm-svn: 37851
2007-07-03 14:03:57 +00:00
Dan Gohman 9a70823375 Teach GetNegatedExpression to negate 0-B to B in UnsafeFPMath mode, and
visitFSUB to fold 0-B to -B in UnsafeFPMath mode. Also change visitFNEG
to use isNegatibleForFree/GetNegatedExpression instead of doing a subset
of the same thing manually.

This fixes test/CodeGen/X86/negative-sin.ll.

llvm-svn: 37842
2007-07-02 15:48:56 +00:00
Dan Gohman a866514528 Generalize MVT::ValueType and associated functions to be able to represent
extended vector types. Remove the special SDNode opcodes used for pre-legalize
vector operations, and the special MVT::Vector type used with them. Adjust
lowering and legalize to work with the normal SDNode kinds instead, and to
use the normal MVT functions to work with vector types instead of using the
two special operands that the pre-legalize nodes held.

This allows pre-legalize and post-legalize DAGs, and the code that operates
on them, to be more consistent. Pre-legalize vector operators can be handled
more consistently with scalar operators. And, -view-dag-combine1-dags and
-view-legalize-dags now look prettier for vector code.

llvm-svn: 37719
2007-06-25 16:23:39 +00:00
Dan Gohman 309d3d51b3 Move ComputeMaskedBits, MaskedValueIsZero, and ComputeNumSignBits from
TargetLowering to SelectionDAG so that they have more convenient
access to the current DAG, in preparation for the ValueType routines
being changed from standalone functions to members of SelectionDAG for
the pre-legalize vector type changes.

llvm-svn: 37704
2007-06-22 14:59:07 +00:00
Evan Cheng aa5f5d960d Xforms:
(add (select cc, 0, c), x) -> (select cc, x, (add, x, c))
(sub x, (select cc, 0, c)) -> (select cc, x, (sub, x, c))

llvm-svn: 37685
2007-06-21 07:39:16 +00:00
Dan Gohman a7644dd9b9 Pass a SelectionDAG into SDNode::dump everywhere it's used, in prepration
for needing the DAG node to print pre-legalize extended value types, and
to get better debug messages with target-specific nodes.

llvm-svn: 37656
2007-06-19 14:13:56 +00:00
Dan Gohman 5c4413120f Rename MVT::getVectorBaseType to MVT::getVectorElementType.
llvm-svn: 37579
2007-06-14 22:58:02 +00:00
Chris Lattner 4698083b96 tighten up recursion depth again
llvm-svn: 37330
2007-05-25 02:19:06 +00:00
Evan Cheng a4d187b8ce Fix a typo that caused combiner to create mal-formed pre-indexed store where value store is the same as the base pointer.
llvm-svn: 37318
2007-05-24 02:35:39 +00:00
Chris Lattner 6509c0673f prevent exponential recursion in isNegatibleForFree
llvm-svn: 37310
2007-05-23 07:35:22 +00:00
Dan Gohman b539df3389 Qualify calls to getTypeForValueType with MVT:: too.
llvm-svn: 37233
2007-05-18 18:41:29 +00:00
Dale Johannesen 7a6c175e7a Don't fold bitconvert(load) for preinc/postdec loads. Likewise stores.
llvm-svn: 37130
2007-05-16 22:45:30 +00:00
Chris Lattner 48fb92f75d Use a ptr set instead of a linear search to unique TokenFactor operands.
This fixes PR1423

llvm-svn: 37102
2007-05-16 06:37:59 +00:00
Evan Cheng 288f133c71 Bug fix: should check ABI alignment, not pref. alignment.
llvm-svn: 37094
2007-05-16 02:04:50 +00:00
Lauro Ramos Venancio 3f142cbca2 Fix an infinite recursion in GetNegatedExpression.
llvm-svn: 37086
2007-05-15 17:05:43 +00:00
Chris Lattner e49c974a7c implement a simple fneg optimization/propagation thing. This compiles:
CodeGen/PowerPC/fneg.ll into:

_t4:
        fmul f0, f3, f4
        fmadd f1, f1, f2, f0
        blr

instead of:

_t4:
        fneg f0, f3
        fmul f0, f0, f4
        fmsub f1, f1, f2, f0
        blr

llvm-svn: 37054
2007-05-14 22:04:50 +00:00
Evan Cheng f325c2a65e Can't fold the bit_convert is the store is a truncating store.
llvm-svn: 36962
2007-05-09 21:49:47 +00:00
Evan Cheng 562e45692e Forgot a check.
llvm-svn: 36910
2007-05-07 21:36:06 +00:00
Evan Cheng a4cf58a103 Enable a couple of xforms:
- (store (bitconvert v)) -> (store v) if resultant store does not require
higher alignment
- (bitconvert (load v)) -> (load (bitconvert*)v) if resultant load does not
require higher alignment

llvm-svn: 36908
2007-05-07 21:27:48 +00:00
Evan Cheng 044a0a8cfb Don't create indexed load / store with zero offset!
llvm-svn: 36716
2007-05-03 23:52:19 +00:00
Evan Cheng b68343cdd8 Forgot about chain result; also UNDEF cannot have multiple values.
llvm-svn: 36622
2007-05-01 08:53:39 +00:00
Evan Cheng a684cd23a5 * Only turn a load to UNDEF if all of its outputs have no uses (indexed loads
produce two results.)
* Do not touch volatile loads.

llvm-svn: 36604
2007-05-01 00:38:21 +00:00
Christopher Lamb 8af6d5896f PR400 phase 2. Propagate attributed load/store information through DAGs.
llvm-svn: 36356
2007-04-22 23:15:30 +00:00
Reid Spencer 0c1349e6bc Revert Christopher Lamb's load/store alignment changes.
llvm-svn: 36309
2007-04-21 18:36:27 +00:00
Christopher Lamb bff50208c8 add support for alignment attributes on load/store instructions
llvm-svn: 36301
2007-04-21 08:16:25 +00:00
Chris Lattner f03c90bee6 allow SRL to simplify its operands, as it doesn't demand all bits as input.
llvm-svn: 36245
2007-04-18 03:06:49 +00:00
Chris Lattner bf14f20632 When replacing a node in SimplifyDemandedBits, if the old node used any
single-use nodes, they will be dead soon.  Make sure to remove them before
processing other nodes.  This implements CodeGen/X86/shl_elim.ll

llvm-svn: 36244
2007-04-18 03:05:22 +00:00
Chris Lattner 9ad5915559 SIGN_EXTEND_INREG does not demand its top bits. Give SimplifyDemandedBits
a chance to hack on it.  This compiles:

int baz(long long a) { return (short)(((int)(a >>24)) >> 9); }

into:
_baz:
        slwi r2, r3, 8
        srwi r2, r2, 9
        extsh r3, r2
        blr

instead of:

_baz:
        srwi r2, r4, 24
        rlwimi r2, r3, 8, 0, 23
        srwi r2, r2, 9
        extsh r3, r2
        blr

This implements CodeGen/PowerPC/sign_ext_inreg1.ll

llvm-svn: 36212
2007-04-17 19:03:21 +00:00
Chris Lattner 18e4ac4107 fix an infinite loop compiling ldecod, notice by JeffC.
llvm-svn: 35910
2007-04-11 16:51:53 +00:00
Chris Lattner a083ffcad7 Fix this harder.
llvm-svn: 35888
2007-04-11 06:50:51 +00:00
Chris Lattner c5f85d3738 don't create shifts by zero, fix some problems with my previous patch
llvm-svn: 35887
2007-04-11 06:43:25 +00:00
Chris Lattner 65786b078c Teach the codegen to turn [aez]ext (setcc) -> selectcc of 1/0, which often
allows other simplifications.  For example, this compiles:
int isnegative(unsigned int X) {
   return !(X < 2147483648U);
}

Into this code:

x86:
        movl 4(%esp), %eax
        shrl $31, %eax
        ret
arm:
        mov r0, r0, lsr #31
        bx lr
thumb:
        lsr r0, r0, #31
        bx lr

instead of:

x86:
        cmpl $0, 4(%esp)
        sets %al
        movzbl %al, %eax
        ret

arm:
        mov r3, #0
        cmp r0, #0
        movlt r3, #1
        mov r0, r3
        bx lr

thumb:
        mov r2, #1
        mov r1, #0
        cmp r0, #0
        blt LBB1_2      @entry
LBB1_1: @entry
        cpy r2, r1
LBB1_2: @entry
        cpy r0, r2
        bx lr

Testcase here: test/CodeGen/Generic/ispositive.ll

llvm-svn: 35883
2007-04-11 05:32:27 +00:00
Chris Lattner 41189c63cc Codegen integer abs more efficiently using the trick from the PPC CWG. This
improves codegen on many architectures.  Tests committed as CodeGen/*/iabs.ll

X86 Old:			X86 New:
_test:				_test:
   movl 4(%esp), %ecx		   movl 4(%esp), %eax
   movl %ecx, %eax		   movl %eax, %ecx
   negl %eax			   sarl $31, %ecx
   testl %ecx, %ecx		   addl %ecx, %eax
   cmovns %ecx, %eax		   xorl %ecx, %eax
   ret				   ret

PPC Old:			PPC New:
_test:				_test:
   cmpwi cr0, r3, -1		   srawi r2, r3, 31
   neg r2, r3			   add r3, r3, r2
   bgt cr0, LBB1_2 ;		   xor r3, r3, r2
LBB1_1: ;			   blr
   mr r3, r2
LBB1_2: ;
   blr

ARM Old:			ARM New:
_test:				_test:
   rsb r3, r0, #0		   add r3, r0, r0, asr #31
   cmp r0, #0			   eor r0, r3, r0, asr #31
   movge r3, r0			   bx lr
   mov r0, r3
   bx lr

Thumb Old:			Thumb New:
_test:				_test:
   neg r2, r0			   asr r2, r0, #31
   cmp r0, #0			   add r0, r0, r2
   bge LBB1_2			   eor r0, r2
LBB1_1: @			   bx lr
   cpy r0, r2
LBB1_2: @
   bx lr


Sparc Old:			Sparc New:
test:				test:
   save -96, %o6, %o6		   save -96, %o6, %o6
   sethi 0, %l0			   sra %i0, 31, %l0
   sub %l0, %i0, %l0		   add %i0, %l0, %l1
   subcc %i0, -1, %l1		   xor %l1, %l0, %i0
   bg .BB1_2			   restore %g0, %g0, %g0
   nop				   retl
.BB1_1:				   nop
   or %g0, %l0, %i0
.BB1_2:
   restore %g0, %g0, %g0
   retl
   nop

It also helps alpha/ia64 :)

llvm-svn: 35881
2007-04-11 05:11:38 +00:00
Scott Michel 16627a542f 1. Insert custom lowering hooks for ISD::ROTR and ISD::ROTL.
2. Help DAGCombiner recognize zero/sign/any-extended versions of ROTR and ROTL
patterns. This was motivated by the X86/rotate.ll testcase, which should now
generate code for other platforms (and soon-to-come platforms.) Rewrote code
slightly to make it easier to read.

llvm-svn: 35605
2007-04-02 21:36:32 +00:00
Dale Johannesen 4bbd2eefba Fix incorrect combination of different loads. Reenable zext-over-truncate
combination.

llvm-svn: 35517
2007-03-30 21:38:07 +00:00
Evan Cheng ccee35fd0d Disable load width reduction xform of variant (zext (truncate load x)) for
big endian targets until llvm-gcc build issue has been resolved.

llvm-svn: 35449
2007-03-29 07:56:46 +00:00
Evan Cheng 8275f0e0af SIGN_EXTEND_INREG requires one extra operand, a ValueType node.
llvm-svn: 35350
2007-03-26 07:12:51 +00:00
Evan Cheng b7051f596a Adjust offset to compensate for big endian machines.
llvm-svn: 35293
2007-03-24 00:02:43 +00:00
Evan Cheng a883b58caf Make sure SEXTLOAD of the specific type is supported on the target.
llvm-svn: 35289
2007-03-23 22:13:36 +00:00
Evan Cheng e2f5f24e8e Also replace uses of SRL if that's also folded during ReduceLoadWidth().
llvm-svn: 35286
2007-03-23 20:55:21 +00:00
Evan Cheng a824e79f06 A couple of bug fixes for reducing load width xform:
1. Address offset is in bytes.
2. Make sure truncate node uses are replaced with new load.

llvm-svn: 35274
2007-03-23 02:16:52 +00:00
Evan Cheng 464dc9b74c More opportunities to reduce load size.
llvm-svn: 35254
2007-03-22 01:54:19 +00:00
Evan Cheng d63baead9b fold (truncate (srl (load x), c)) -> (smaller load (x+c/vt bits))
llvm-svn: 35239
2007-03-21 20:14:05 +00:00
Evan Cheng 8a1d09d079 Avoid combining indexed load further.
llvm-svn: 35005
2007-03-07 08:07:03 +00:00
Chris Lattner 47206667c0 fold away addc nodes when we know there cannot be a carry-out.
llvm-svn: 34913
2007-03-04 20:40:38 +00:00