Bill Wendling 43a6c5e2fc We have a chance for an optimization. Consider this code: ...

int x(int t) {
  if (t & 256)
    return -26;
  return 0;
}

We generate this:

     tst.w   r0, #256
     mvn     r0, #25
     it      eq
     moveq   r0, #0

while gcc generates this:

     ands    r0, r0, #256
     it      ne
     mvnne   r0, #25
     bx      lr

Scandalous really!

During ISel time, we can look for this particular pattern. One where we have a
"MOVCC" that uses the flag off of a CMPZ that itself is comparing an AND
instruction to 0. Something like this (greatly simplified):

  %r0 = ISD::AND ...
  ARMISD::CMPZ %r0, 0         @ sets [CPSR]
  %r0 = ARMISD::MOVCC 0, -26  @ reads [CPSR]

All we have to do is convert the "ISD::AND" into an "ARM::ANDS" that sets [CPSR]
when it's zero. The zero value will all ready be in the %r0 register and we only
need to change it if the AND wasn't zero. Easy!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112664 91177308-0d34-0410-b5e6-96231b3b80d8

2010-08-31 22:41:22 +00:00

..

2009-07-17-CrossRegClassCopy.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-07-21-ISelBug.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-07-23-CPIslandBug.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-07-30-PEICrash.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-08-01-WrongLDRBOpc.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-08-02-CoalescerBug.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-08-04-CoalescerAssert.ll

Remove the arm_aapcscc marker from the tests. It is the default

2010-06-15 19:04:29 +00:00

2009-08-04-CoalescerBug.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-08-04-ScavengerAssert.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-08-04-SubregLoweringBug2.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-08-04-SubregLoweringBug3.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-08-04-SubregLoweringBug.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-08-06-SpDecBug.ll

Remove the arm_aapcscc marker from the tests. It is the default

2010-06-15 19:04:29 +00:00

2009-08-07-CoalescerBug.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

2009-08-07-NeonFPBug.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-08-08-ScavengerAssert.ll

Remove the arm_aapcscc marker from the tests. It is the default

2010-06-15 19:04:29 +00:00

2009-08-10-ISelBug.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-09-28-ITBlockBug.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-10-15-ITBlockBranch.ll

Fix test to appease the buildbots.

2010-07-14 16:43:47 +00:00

2009-11-01-CopyReg2RegBug.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-11-11-ScavengerAssert.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-11-13-STRDBug.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2009-12-01-LoopIVUsers.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2010-01-06-TailDuplicateLabels.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2010-01-19-RemovePredicates.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2010-02-11-phi-cycle.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2010-02-24-BigStack.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2010-03-08-addi12-ccout.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2010-03-15-AsmCCClobber.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2010-04-15-DynAllocBug.ll

Many Thumb2 instructions can reference the full ARM register set (i.e.,

2010-07-30 02:41:01 +00:00

2010-04-26-CopyRegCrash.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2010-05-24-rsbs.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2010-06-14-NEONCoalescer.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

2010-06-19-ITBlockCrash.ll

Fix a crash caused by dereference of MBB.end(). rdar://8110842

2010-06-20 00:54:38 +00:00

2010-06-21-TailMergeBug.ll

Tail merging pass shall not break up IT blocks. rdar://8115404

2010-06-22 01:18:16 +00:00

2010-08-10-VarSizedAllocaBug.ll

Re-apply r110655 with fixes. Epilogue must restore sp from fp if the function stack frame has a var-sized object.

2010-08-10 19:30:19 +00:00

bfi.ll

Add combiner patterns to more effectively utilize the BFI (bitfield insert)

2010-07-17 03:30:54 +00:00

bfx.ll

Update ARM DAGtoDAG for matching UBFX instruction for unsigned bitfield

2010-04-22 23:24:18 +00:00

carry.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

cortex-fp.ll

fix silly typo

2010-08-11 17:32:46 +00:00

crash.ll

Add alignment arguments to all the NEON load/store intrinsics.

2010-08-27 17:13:24 +00:00

cross-rc-coalescing-1.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

cross-rc-coalescing-2.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

dg.exp

…

div.ll

Report error if codegen tries to instantiate a ARM target when the cpu does support it. e.g. cortex-m* processors.

2010-08-11 07:17:46 +00:00

frameless2.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

frameless.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

ifcvt-neon.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

large-stack.ll

Stop using the old pre-UAL syntax for LDM/STM instruction suffixes.

2010-03-16 16:19:07 +00:00

ldr-str-imm12.ll

Eliminate the first have of the optimization which eliminates BRCOND

2010-06-24 15:04:11 +00:00

load-global.ll

Start function numbering at 0.

2010-04-17 16:29:15 +00:00

lsr-deficiency.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

machine-licm-vdup.ll

Add alignment arguments to all the NEON load/store intrinsics.

2010-08-27 17:13:24 +00:00

machine-licm.ll

Add alignment arguments to all the NEON load/store intrinsics.

2010-08-27 17:13:24 +00:00

mul_const.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

pic-load.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

thumb2-adc.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-add2.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-add3.ll

Convert Thumb2 tests to FileCheck for PR5307.

2009-11-22 15:18:27 +00:00

thumb2-add4.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-add5.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-add6.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-add.ll

Delete useless trailing semicolons.

2010-01-05 17:55:26 +00:00

thumb2-and2.ll

update tests for smarter BIC usage

2010-07-20 16:16:48 +00:00

thumb2-and.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-asr2.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-asr.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-badreg-operands.ll

Many Thumb2 instructions can reference the full ARM register set (i.e.,

2010-07-30 02:41:01 +00:00

thumb2-barrier.ll

- Add subtarget feature -mattr=+db which determine whether an ARM cpu has the

2010-08-11 06:22:01 +00:00

thumb2-bcc.ll

Fix tests.

2009-11-01 18:13:29 +00:00

thumb2-bfc.ll

Fix Thumb2 failures by converting them to FileCheck.

2009-10-27 06:31:02 +00:00

thumb2-bic.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-branch.ll

Fix a bug which prevented tail merging of return instructions in

2010-05-03 14:35:47 +00:00

thumb2-call-tc.ll

Temporarily disable tail calls on ARM to work around some linker problems.

2010-08-13 22:43:33 +00:00

thumb2-call.ll

Remove tail call to preserve this test. A tail

2010-06-03 21:57:48 +00:00

thumb2-cbnz.ll

Allow ARM if-converter to be run after post allocation scheduling.

2010-06-18 23:09:54 +00:00

thumb2-clz.ll

Fix Thumb2 failures by converting them to FileCheck.

2009-10-27 06:31:02 +00:00

thumb2-cmn2.ll

Fix Thumb2 failures by converting them to FileCheck.

2009-10-27 06:31:02 +00:00

thumb2-cmn.ll

Convert Thumb2 tests to FileCheck for PR5307.

2009-11-22 15:18:27 +00:00

thumb2-cmp2.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-cmp.ll

ARM/Thumb2: Fix a misselect in getARMCmp, when attempting to adjust a signed

2010-08-25 16:58:05 +00:00

thumb2-eor2.ll

Fix Thumb2 failures by converting them to FileCheck.

2009-10-27 06:31:02 +00:00

thumb2-eor.ll

PR7458: Try commuting Thumb2 instruction operands to put them into 2-address

2010-06-24 16:50:20 +00:00

thumb2-ifcvt1-tc.ll

Temporarily disable tail calls on ARM to work around some linker problems.

2010-08-13 22:43:33 +00:00

thumb2-ifcvt1.ll

Remove tail call. A tail call version will follow.

2010-06-04 00:03:37 +00:00

thumb2-ifcvt2.ll

Allow ARM if-converter to be run after post allocation scheduling.

2010-06-18 23:09:54 +00:00

thumb2-ifcvt3.ll

Reapply my if-conversion cleanup from svn r106939 with fixes.

2010-06-29 00:55:23 +00:00

thumb2-jtb.ll

Enable arm jumpt table adjustment.

2009-11-17 21:24:11 +00:00

thumb2-ldm.ll

Make this test not use tail calls. A tail call

2010-06-03 21:53:01 +00:00

thumb2-ldr_ext.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-ldr_post.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-ldr_pre.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-ldr.ll

Added sub-formats to the NeonI/NeonXI instructions to further refine the NEONFrm

2010-03-17 17:52:21 +00:00

thumb2-ldrb.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-ldrd.ll

Enable pre-regalloc load / store multiple pass for Thumb2.

2009-09-27 09:46:04 +00:00

thumb2-ldrh.ll

Added sub-formats to the NeonI/NeonXI instructions to further refine the NEONFrm

2010-03-17 17:52:21 +00:00

thumb2-lsl2.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-lsl.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-lsr2.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-lsr3.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-lsr.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-mla.ll

Convert Thumb2 tests to FileCheck for PR5307.

2009-11-22 15:18:27 +00:00

thumb2-mls.ll

Convert Thumb2 tests to FileCheck for PR5307.

2009-11-22 15:18:27 +00:00

thumb2-mov.ll

Consolidate test files

2009-10-31 22:20:56 +00:00

thumb2-mul.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-mulhi.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-mvn2.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-mvn.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-mvncc.ll

We have a chance for an optimization. Consider this code:

2010-08-31 22:41:22 +00:00

thumb2-neg.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-orn2.ll

Convert Thumb2 tests to FileCheck for PR5307.

2009-11-22 15:18:27 +00:00

thumb2-orn.ll

Miss two, PR5307.

2009-11-22 15:35:28 +00:00

thumb2-orr2.ll

Miss two, PR5307.

2009-11-22 15:35:28 +00:00

thumb2-orr.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-pack.ll

Change ARM PKHTB and PKHBT instructions to use a shift_imm operand to avoid

2010-08-17 17:23:19 +00:00

thumb2-rev16.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-rev.ll

Cleanup of ARMv7M support. Move hardware divide and Thumb2 extract/pack

2010-05-05 23:44:43 +00:00

thumb2-ror2.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-ror.ll

Convert Thumb2 tests to FileCheck for PR5307.

2009-11-22 15:18:27 +00:00

thumb2-rsb2.ll

Convert Thumb2 tests to FileCheck for PR5307.

2009-11-22 15:18:27 +00:00

thumb2-rsb.ll

Convert Thumb2 tests to FileCheck for PR5307.

2009-11-22 15:18:27 +00:00

thumb2-sbc.ll

Improve 64-subtraction of immediates when parts of the immediate can fit

2010-07-14 17:45:16 +00:00

thumb2-select_xform.ll

Move ARM if-conversion before post-ra scheduling.

2010-06-18 23:32:07 +00:00

thumb2-select.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-shifter.ll

Cleanup of ARMv7M support. Move hardware divide and Thumb2 extract/pack

2010-05-05 23:44:43 +00:00

thumb2-smla.ll

Cleanup of ARMv7M support. Move hardware divide and Thumb2 extract/pack

2010-05-05 23:44:43 +00:00

thumb2-smul.ll

Cleanup of ARMv7M support. Move hardware divide and Thumb2 extract/pack

2010-05-05 23:44:43 +00:00

thumb2-spill-q.ll

Add alignment arguments to all the NEON load/store intrinsics.

2010-08-27 17:13:24 +00:00

thumb2-str_post.ll

Fix Thumb2 failures by converting them to FileCheck.

2009-10-27 06:31:02 +00:00

thumb2-str_pre.ll

Added sub-formats to the NeonI/NeonXI instructions to further refine the NEONFrm

2010-03-17 17:52:21 +00:00

thumb2-str.ll

Added sub-formats to the NeonI/NeonXI instructions to further refine the NEONFrm

2010-03-17 17:52:21 +00:00

thumb2-strb.ll

Added sub-formats to the NeonI/NeonXI instructions to further refine the NEONFrm

2010-03-17 17:52:21 +00:00

thumb2-strh.ll

Added sub-formats to the NeonI/NeonXI instructions to further refine the NEONFrm

2010-03-17 17:52:21 +00:00

thumb2-sub2.ll

Convert Thumb2 tests to FileCheck for PR5307.

2009-11-22 15:18:27 +00:00

thumb2-sub3.ll

Improve 64-subtraction of immediates when parts of the immediate can fit

2010-07-14 17:45:16 +00:00

thumb2-sub4.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-sub5.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-sub.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-sxt_rot.ll

Cleanup of ARMv7M support. Move hardware divide and Thumb2 extract/pack

2010-05-05 23:44:43 +00:00

thumb2-tbb.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-tbh.ll

Remove arm_apcscc from the test files. It is the default and doing this

2010-06-17 15:18:27 +00:00

thumb2-teq2.ll

Convert to FileCheck

2009-11-16 20:04:15 +00:00

thumb2-teq.ll

Convert Thumb2 tests to FileCheck for PR5307.

2009-11-22 15:18:27 +00:00

thumb2-tst2.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

thumb2-tst.ll

Convert Thumb2 tests to FileCheck for PR5307.

2009-11-22 15:18:27 +00:00

thumb2-uxt_rot.ll

Cleanup of ARMv7M support. Move hardware divide and Thumb2 extract/pack

2010-05-05 23:44:43 +00:00

thumb2-uxtb.ll

update tests for smarter BIC usage

2010-07-20 16:16:48 +00:00

tls1.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00

tls2.ll

Eliminate more uses of llvm-as and llvm-dis.

2009-09-09 00:09:15 +00:00