Commit Graph

172 Commits

Author SHA1 Message Date
Evan Cheng 1596f7f6f3 Fix r114632. Return if the only terminator is an unconditional branch after the redundant ones are deleted.
llvm-svn: 114688
2010-09-23 19:42:03 +00:00
Evan Cheng 66c8cd2b32 If there are multiple unconditional branches terminating a block, eliminate all
but the first one. Those will never be executed. There was logic to do this
but it was faulty.

llvm-svn: 114632
2010-09-23 06:54:40 +00:00
Evan Cheng d757c88bba OptimizeCompareInstr should avoid iterating pass the beginning of the MBB when the 'and' instruction is after the comparison.
llvm-svn: 114506
2010-09-21 23:49:07 +00:00
Gabor Greif 1a25ae88ff Fix buglet when the TST instruction directly uses the AND result.
I am unable to write a test for this case, help is solicited, though...
What I did is to tickle the code in the debugger and verify that we do the right thing.

llvm-svn: 114430
2010-09-21 13:30:57 +00:00
Gabor Greif adbbb93d3d Move the search for the appropriate AND instruction
into OptimizeCompareInstr.
This necessitates the passing of CmpValue around,
so widen the virtual functions to accomodate.

No functionality changes.

llvm-svn: 114428
2010-09-21 12:01:15 +00:00
Chris Lattner e3d864b857 convert targets to the new MF.getMachineMemOperand interface.
llvm-svn: 114391
2010-09-21 04:39:43 +00:00
Jakob Stoklund Olesen 44857a38fa Remember VLDMQ.
llvm-svn: 114026
2010-09-15 21:40:11 +00:00
Jakob Stoklund Olesen b929c7173d Add missing break.
llvm-svn: 114025
2010-09-15 21:40:09 +00:00
Jakob Stoklund Olesen 33005d1327 Recognize VST1q64Pseudo and VSTMQ as stack slot stores.
Recognize VLD1q64Pseudo as a stack slot load.

Reject these if they are loading or storing a subregister. The API (and
VirtRegRewriter) doesn't know how to deal with that.

llvm-svn: 113985
2010-09-15 17:27:09 +00:00
Bob Wilson 660d7ecf32 Reapply Gabor's 113839, 113840, and 113876 with a fix for a problem
encountered while building llvm-gcc for arm.  This is probably the same issue
that the ppc buildbot hit. llvm::prior works on a MachineBasicBlock::iterator,
not a plain MachineInstr.

llvm-svn: 113983
2010-09-15 17:12:08 +00:00
Gabor Greif 9ae4b271f2 the darwin9-powerpc buildbot keeps consistently crashing,
backing out following to get it back to green,
so I can investigate in peace:

svn merge -c -113840  llvm/test/CodeGen/ARM/arm-and-tst-peephole.ll
svn merge -c -113876 -c -113839 llvm/lib/Target/ARM/ARMBaseInstrInfo.cpp

llvm-svn: 113980
2010-09-15 16:53:07 +00:00
Jakob Stoklund Olesen 11f5be3b86 Move ARM is{LoadFrom,StoreTo}StackSlot closer to their siblings so they won't be
forgotten in the future.

Coalesce identical cases in switch.

No functional changes intended.

llvm-svn: 113979
2010-09-15 16:36:26 +00:00
Bob Wilson 2c00b5098a Spelling fix.
llvm-svn: 113978
2010-09-15 16:28:21 +00:00
Bob Wilson b1e9d4bff1 Use VLD1/VST1 pseudo instructions for loadRegFromStackSlot and
storeRegToStackSlot.

llvm-svn: 113918
2010-09-15 01:48:05 +00:00
Gabor Greif b54e9387ab an attempt to salvage the darwin9-powerpc buildbot, which could be miscompiling this line
llvm-svn: 113876
2010-09-14 22:25:16 +00:00
Gabor Greif d0cef1e2ef Eliminate a 'tst' that immediately follows an 'and'
by morphing the 'and' to its recording form 'andS'.

This is basically a test commit into this area, to
see whether the bots like me. Several generalizations
can be applied and various avenues of code simplification
are open. I'll introduce those as I go.

I am aware of stylistic input from Bill Wendling, about
where put the analysis complexity, but I am positive
that we can move things around easily and will find a
satisfactory solution.

llvm-svn: 113839
2010-09-14 09:23:22 +00:00
Bill Wendling 27dddd1fd1 Rename ConvertToSetZeroFlag to something more general.
llvm-svn: 113670
2010-09-11 00:13:50 +00:00
Bill Wendling d0a5f4e238 No need to recompute the SrcReg and CmpValue.
llvm-svn: 113666
2010-09-10 23:46:12 +00:00
Bill Wendling 041230014c Move some of the decision logic for converting an instruction into one that sets
the 'zero' bit down into the back-end. There are other cases where this logic
isn't sufficient, so they should be handled separately.

llvm-svn: 113665
2010-09-10 23:34:19 +00:00
Bill Wendling aee679bf35 Modify the comparison optimizations in the peephole optimizer to update the
iterator when an optimization took place. This allows us to do more insane
things with the code than just remove an instruction or two.

llvm-svn: 113640
2010-09-10 21:55:43 +00:00
Jim Grosbach 1f77ee5691 Add a missing case to duplicateCPV() for LSDA constants. Add a FIXME. rdar://8302157
llvm-svn: 113637
2010-09-10 21:38:22 +00:00
Evan Cheng bf4070756f Teach if-converter to be more careful with predicating instructions that would
take multiple cycles to decode.
For the current if-converter clients (actually only ARM), the instructions that
are predicated on false are not nops. They would still take machine cycles to
decode. Micro-coded instructions such as LDM / STM can potentially take multiple
cycles to decode. If-converter should take treat them as non-micro-coded
simple instructions.

llvm-svn: 113570
2010-09-10 01:29:16 +00:00
Evan Cheng 367a5df8cf For each instruction itinerary class, specify the number of micro-ops each
instruction in the class would be decoded to. Or zero if the number of
uOPs must be determined dynamically.

This will be used to determine the cost-effectiveness of predicating a
micro-coded instruction.

llvm-svn: 113513
2010-09-09 18:18:55 +00:00
Jim Grosbach 19cb2f4c67 remove obsolete comment
llvm-svn: 113337
2010-09-08 03:51:44 +00:00
Jim Grosbach 136d035e45 correct spill code to properly determine if dynamic stack realignment is
present in the function and thus whether aligned load/store instructions can
be used.

llvm-svn: 113323
2010-09-08 00:26:59 +00:00
Bob Wilson 13ce07fa92 Change ARM VFP VLDM/VSTM instructions to use addressing mode #4, just like
all the other LDM/STM instructions.  This fixes asm printer crashes when
compiling with -O0.  I've changed one of the NEON tests (vst3.ll) to run
with -O0 to check this in the future.

Prior to this change VLDM/VSTM used addressing mode #5, but not really.
The offset field was used to hold a count of the number of registers being
loaded or stored, and the AM5 opcode field was expanded to specify the IA
or DB mode, instead of the standard ADD/SUB specifier.  Much of the backend
was not aware of these special cases.  The crashes occured when rewriting
a frameindex caused the AM5 offset field to be changed so that it did not
have a valid submode.  I don't know exactly what changed to expose this now.
Maybe we've never done much with -O0 and NEON.  Regardless, there's no longer
any reason to keep a count of the VLDM/VSTM registers, so we can use
addressing mode #4 and clean things up in a lot of places.

llvm-svn: 112322
2010-08-27 23:18:17 +00:00
Bill Wendling ad2aa57774 Minor simplification. Gets rid of a needless temporary.
llvm-svn: 111430
2010-08-18 21:32:07 +00:00
Bill Wendling 79553bad50 Handle ARM compares as well as converting for ARM adds, subs, and thumb2's adds.
llvm-svn: 110762
2010-08-11 00:23:00 +00:00
Bill Wendling 0757820f8f Turn optimize compares back on with fix. We needed to test that a machine op was
a register before checking if it was defined.

llvm-svn: 110733
2010-08-10 21:38:11 +00:00
Bill Wendling 798617b1ab Use the "isCompare" machine instruction attribute instead of calling the
relatively expensive comparison analyzer on each instruction. Also rename the
comparison analyzer method to something more in line with what it actually does.

This pass is will eventually be folded into the Machine CSE pass.

llvm-svn: 110539
2010-08-08 05:04:59 +00:00
Bill Wendling 7de9d52c13 Add the Optimize Compares pass (disabled by default).
This pass tries to remove comparison instructions when possible. For instance,
if you have this code:

   sub r1, 1
   cmp r1, 0
   bz  L1

and "sub" either sets the same flag as the "cmp" instruction or could be
converted to set the same flag, then we can eliminate the "cmp" instruction all
together. This is a important for ARM where the ALU instructions could set the
CPSR flag, but need a special suffix ('s') to do so.

llvm-svn: 110423
2010-08-06 01:32:48 +00:00
Jim Grosbach d343166a0b Many Thumb2 instructions can reference the full ARM register set (i.e.,
have 4 bits per register in the operand encoding), but have undefined
behavior when the operand value is 13 or 15 (SP and PC, respectively).
The trivial coalescer in linear scan sometimes will merge a copy from
SP into a subsequent instruction which uses the copy, and if that
instruction cannot legally reference SP, we get bad code such as:
  mls r0,r9,r0,sp
instead of:
  mov r2, sp
  mls r0, r9, r0, r2

This patch adds a new register class for use by Thumb2 that excludes
the problematic registers (SP and PC) and is used instead of GPR
for those operands which cannot legally reference PC or SP. The
trivial coalescer explicitly requires that the register class
of the destination for the COPY instruction contain the source
register for the COPY to be considered for coalescing. This prevents
errant instructions like that above.

PR7499

llvm-svn: 109842
2010-07-30 02:41:01 +00:00
Chris Lattner cbe9856fce prune #includes a little.
llvm-svn: 108929
2010-07-20 21:17:29 +00:00
Jakob Stoklund Olesen 8289f78569 Remove the isMoveInstr() hook.
llvm-svn: 108567
2010-07-16 22:35:46 +00:00
Bill Wendling 499f797cdd Rename DBG_LABEL PROLOG_LABEL, because it's only used during prolog emission and
thus is a much more meaningful name.

llvm-svn: 108563
2010-07-16 22:20:36 +00:00
Jakob Stoklund Olesen 0961c55161 RISC architectures get their memory operand folding for free.
The only folding these load/store architectures can do is converting COPY into a
load or store, and the target independent part of foldMemoryOperand already
knows how to do that.

llvm-svn: 108099
2010-07-11 19:19:13 +00:00
Jakob Stoklund Olesen d7b33002dd Replace copyRegToReg with copyPhysReg for ARM.
llvm-svn: 108078
2010-07-11 06:33:54 +00:00
Jakob Stoklund Olesen 7a7b55eb67 Automatically fold COPY instructions into stack load/store.
llvm-svn: 108012
2010-07-09 20:43:13 +00:00
Bob Wilson 1eade1a327 For big-endian systems, VLD2/VST2 with 32-bit vector elements will swap the
words within the 64-bit D registers.  Use VLD1/VST1 with 64-bit elements
instead.

llvm-svn: 107890
2010-07-08 17:44:00 +00:00
Bob Wilson 4c1ca29039 Represent NEON load/store alignments in bytes, not bits.
llvm-svn: 107701
2010-07-06 21:26:18 +00:00
Rafael Espindola 7c510aa7bc Don't create neon moves in CopyRegToReg. NEONMoveFixPass will do the conversion
if profitable.

llvm-svn: 107673
2010-07-06 16:24:34 +00:00
Rafael Espindola 38a7d7cbc3 Add a VT argument to getMinimalPhysRegClass and replace the copy related uses
of getPhysicalRegisterRegClass with it.

If we want to make a copy (or estimate its cost), it is better to use the
smallest class as more efficient operations might be possible.

llvm-svn: 107140
2010-06-29 14:02:34 +00:00
Evan Cheng 02b184de5b Change if-conversion block size limit checks to add some flexibility.
llvm-svn: 106901
2010-06-25 22:42:03 +00:00
Jim Grosbach ba3ece6f27 IT instructions are considered to be scheduling hazards, but are scheduled
with the following instructions. This is done via trickery by considering the
instruction preceding the IT to be the hazard. Care must be taken to ensure
it's the first non-debug instruction, or the presence of debug info will
affect codegen.

Part of the continuing work for rdar://7797940, making ARM code-gen unaffected
by the presence of debug information.

llvm-svn: 106871
2010-06-25 18:43:14 +00:00
Bill Wendling f470747a36 We are missing opportunites to use ldm. Take code like this:
void t(int *cp0, int *cp1, int *dp, int fmd) {
  int c0, c1, d0, d1, d2, d3;
  c0 = (*cp0++ & 0xffff) | ((*cp1++ << 16) & 0xffff0000);
  c1 = (*cp0++ & 0xffff) | ((*cp1++ << 16) & 0xffff0000);
  /* ... */
}

It code gens into something pretty bad. But with this change (analogous to the
X86 back-end), it will use ldm and generate few instructions.

llvm-svn: 106693
2010-06-23 23:00:16 +00:00
Evan Cheng 2d51c7c592 Allow ARM if-converter to be run after post allocation scheduling.
- This fixed a number of bugs in if-converter, tail merging, and post-allocation
  scheduler. If-converter now runs branch folding / tail merging first to
  maximize if-conversion opportunities.
- Also changed the t2IT instruction slightly. It now defines the ITSTATE
  register which is read by instructions in the IT block.
- Added Thumb2 specific hazard recognizer to ensure the scheduler doesn't
  change the instruction ordering in the IT block (since IT mask has been
  finalized). It also ensures no other instructions can be scheduled between
  instructions in the IT block.

This is not yet enabled.

llvm-svn: 106344
2010-06-18 23:09:54 +00:00
Bob Wilson a92e41a50a Rewrite chained if's as switches and replace assertions with llvm_unreachable
(as suggested in radar 8104405).

llvm-svn: 106318
2010-06-18 21:32:42 +00:00
Stuart Hastings 0125b6410a Add a DebugLoc parameter to TargetInstrInfo::InsertBranch(). This
addresses a longstanding deficiency noted in many FIXMEs scattered
across all the targets.

This effectively moves the problem up one level, replacing eleven
FIXMEs in the targets with eight FIXMEs in CodeGen, plus one path
through FastISel where we actually supply a DebugLoc, fixing Radar
7421831.

llvm-svn: 106243
2010-06-17 22:43:56 +00:00
Dale Johannesen 44f9dfc9cf Next round of tail call changes. Register used in a tail
call must not be callee-saved; following x86, add a new
regclass to represent this.  Also fixes a couple of bugs.
Still disabled by default; Thumb doesn't work yet.

llvm-svn: 106053
2010-06-15 22:08:33 +00:00
Bob Wilson 1478142485 VMOVQQ and VMOVQQQQ are pseudo instructions and not predicable.
llvm-svn: 105990
2010-06-15 05:51:27 +00:00