Commit Graph

472 Commits

Author SHA1 Message Date
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
Jim Grosbach
535d3b4e09 remove trailing whitespace
llvm-svn: 113338
2010-09-08 03:54:02 +00:00
Bob Wilson
f65c9ef720 Replace NEON vabdl, vaba, and vabal intrinsics with combinations of the
vabd intrinsic and add and/or zext operations.  In the case of vaba, this
also avoids the need for a DAG combine pattern to combine vabd with add.
Update tests.  Auto-upgrade the old intrinsics.

llvm-svn: 112941
2010-09-03 01:35:08 +00:00
Bob Wilson
38ab35a911 Remove NEON vmull, vmlal, and vmlsl intrinsics, replacing them with multiply,
add, and subtract operations with zero-extended or sign-extended vectors.
Update tests.  Add auto-upgrade support for the old intrinsics.

llvm-svn: 112773
2010-09-01 23:50:19 +00:00
Bill Wendling
0a65116cce Create an ARMISD::AND node. This node is exactly like the "ARM::AND" node, but
it sets the CPSR register.

llvm-svn: 112393
2010-08-29 03:02:11 +00:00
Daniel Dunbar
a54a1b0edf ARM/Thumb2: Fix a misselect in getARMCmp, when attempting to adjust a signed
comparison that would overflow.
 - The other under/overflow cases can't actually happen because the immediates
   which would trigger them are legal (so we don't enter this code), but
   adjusted the style to make it clear the transform is always valid.

llvm-svn: 112053
2010-08-25 16:58:05 +00:00
Bob Wilson
9a511c07e4 Replace the arm.neon.vmovls and vmovlu intrinsics with vector sign-extend and
zero-extend operations.

llvm-svn: 111614
2010-08-20 04:54:02 +00:00
Bob Wilson
fb7eaff759 Expand ZERO_EXTEND operations for NEON vector types.
Testcase from Nick Lewycky.

llvm-svn: 111341
2010-08-18 01:45:52 +00:00
Bob Wilson
411dfad981 Allow more cases of undef shuffle indices and add tests for them.
llvm-svn: 111226
2010-08-17 05:54:34 +00:00
Bob Wilson
c350e7a509 Ignore undef shuffle indices when checking for a VTRN shuffle. Radar 8290937.
llvm-svn: 111208
2010-08-16 23:37:17 +00:00
Bob Wilson
3c9ed76ba5 Temporarily disable tail calls on ARM to work around some linker problems.
llvm-svn: 111050
2010-08-13 22:43:33 +00:00
Jim Grosbach
4d5dc3e7e5 cortex m4 has floating point support, but only single precision.
llvm-svn: 110810
2010-08-11 15:44:15 +00:00
Bill Wendling
6a98131468 Consider this code snippet:
float t1(int argc) {
  return (argc == 1123) ? 1.234f : 2.38213f;
}

We would generate truly awful code on ARM (those with a weak stomach should look
away):

_t1:
  movw   r1, #1123
  movs   r2, #1
  movs   r3, #0
  cmp    r0, r1
  mov.w  r0, #0
  it     eq
  moveq  r0, r2
  movs   r1, #4
  cmp    r0, #0
  it     ne
  movne  r3, r1
  adr    r0, #LCPI1_0
  ldr    r0, [r0, r3]
  bx     lr

The problem was that legalization was creating a cascade of SELECT_CC nodes, for
for the comparison of "argc == 1123" which was fed into a SELECT node for the ?:
statement which was itself converted to a SELECT_CC node. This is because the
ARM back-end doesn't have custom lowering for SELECT nodes, so it used the
default "Expand".

I added a fairly simple "LowerSELECT" to the ARM back-end. It takes care of this
testcase, but can obviously be expanded to include more cases.

Now we generate this, which looks optimal to me:

_t1:
  movw   r1, #1123
  movs   r2, #0
  cmp    r0, r1
  adr    r0, #LCPI0_0
  it     eq
  moveq  r2, #4
  ldr    r0, [r0, r2]
  bx     lr
  .align  2
LCPI0_0:
  .long   1075344593  @ float 2.382130e+00
  .long   1067316150  @ float 1.234000e+00

llvm-svn: 110799
2010-08-11 08:43:16 +00:00
Evan Cheng
6e809de90c - Add subtarget feature -mattr=+db which determine whether an ARM cpu has the
memory and synchronization barrier dmb and dsb instructions.
- Change instruction names to something more sensible (matching name of actual
  instructions).
- Added tests for memory barrier codegen.

llvm-svn: 110785
2010-08-11 06:22:01 +00:00
Evan Cheng
fa16acae44 Delete some unused instructions.
llvm-svn: 110710
2010-08-10 19:36:22 +00:00
Evan Cheng
3f251fb26e Re-apply r110655 with fixes. Epilogue must restore sp from fp if the function stack frame has a var-sized object.
Also added a test case to check for the added benefit of this patch: it's optimizing away the unnecessary restore of sp from fp for some non-leaf functions.

llvm-svn: 110707
2010-08-10 19:30:19 +00:00
Daniel Dunbar
0dd47bfca3 Revert r110655, "Fix ARM hasFP() semantics. It should return true whenever FP
register is", it breaks a couple test-suite tests.

llvm-svn: 110701
2010-08-10 18:32:02 +00:00
Evan Cheng
8d5d1c1331 Fix ARM hasFP() semantics. It should return true whenever FP register is
reserved, not available for general allocation. This eliminates all the
extra checks for Darwin.

This change also fixes the use of FP to access frame indices in leaf
functions and cleaned up some confusing code in epilogue emission.

llvm-svn: 110655
2010-08-10 06:26:49 +00:00
Dale Johannesen
21f13209f8 Remove switch for disabling ARM tail calls. They
seem to be working correctly.  No functional change.

llvm-svn: 110226
2010-08-04 18:07:17 +00:00
Bob Wilson
79daf7e0ae Combine NEON VABD (absolute difference) intrinsics with ADDs to make VABA
(absolute difference with accumulate) intrinsics.  Radar 8228576.

llvm-svn: 110170
2010-08-04 00:12:08 +00:00
Nate Begeman
b69b182191 Add support for getting & setting the FPSCR application register on ARM when VFP is enabled.
Add support for using the FPSCR in conjunction with the vcvtr instruction, for controlling fp to int rounding.
Add support for the FLT_ROUNDS_ node now that the FPSCR is exposed.

llvm-svn: 110152
2010-08-03 21:31:55 +00:00
Bob Wilson
728eb292eb Refactor ARM-specific DAG combining in preparation for adding some more
transformations.

llvm-svn: 109800
2010-07-29 20:34:14 +00:00
Dale Johannesen
2bff50546c Implement vector constants which are splat of
integers with mov + vdup.  8003375.  This is
currently disabled by default because LICM will
not hoist a VDUP, so it pessimizes the code if
the construct occurs inside a loop (8248029).

llvm-svn: 109799
2010-07-29 20:10:08 +00:00
Anton Korobeynikov
19edda0323 Hook in GlobalMerge pass
llvm-svn: 109359
2010-07-24 21:52:08 +00:00
Jim Grosbach
0acbcb1a60 Use the appropriate register class for an i32 when adding ARM::LR to the
function live in set. This will give us tGPR for Thumb1 and GPR otherwise,
so the copy will be spillable. rdar://8224931

llvm-svn: 109293
2010-07-23 23:50:35 +00:00
Evan Cheng
df907f4594 - Allow target to specify when is register pressure "too high". In most cases,
it's too late to start backing off aggressive latency scheduling when most
  of the registers are in use so the threshold should be a bit tighter.
- Correctly handle live out's and extract_subreg etc.
- Enable register pressure aware scheduling by default for hybrid scheduler.
  For ARM, this is almost always a win on # of instructions. It's runtime
  neutral for most of the tests. But for some kernels with high register
  pressure it can be a huge win. e.g. 464.h264ref reduced number of spills by
  54 and sped up by 20%.

llvm-svn: 109279
2010-07-23 22:39:59 +00:00
Chandler Carruth
a1d7516cb7 Mark an assert-only variable as used.
llvm-svn: 109091
2010-07-22 08:02:25 +00:00
Evan Cheng
285903853f More register pressure aware scheduling work.
llvm-svn: 109064
2010-07-21 23:53:58 +00:00
Eric Christopher
84bdfd80df Baby steps towards ARM fast-isel.
llvm-svn: 109047
2010-07-21 22:26:11 +00:00
Rafael Espindola
4277e14dc4 Fix calling convention on ARM if vfp2+ is enabled.
llvm-svn: 109009
2010-07-21 11:38:30 +00:00
Evan Cheng
a77f3d3b37 Teach bottom up pre-ra scheduler to track register pressure. Work in progress.
llvm-svn: 108991
2010-07-21 06:09:07 +00:00
Jim Grosbach
9c7708cc1b Removed un-used code.
llvm-svn: 108841
2010-07-20 14:51:32 +00:00
Evan Cheng
10f99a3490 ARM has to provide its own TargetLowering::findRepresentativeClass because its scalar floating point registers alias its vector registers.
llvm-svn: 108761
2010-07-19 22:15:08 +00:00
Jim Grosbach
8d3ba7349c Since ARM emits inline jump tables as part of the ConstantIsland pass,
it should set the jump table encloding the EK_Inline. This prevents
a second, unused, copy of the table from being emitted after the function
body. PR6581.

llvm-svn: 108730
2010-07-19 17:20:38 +00:00
Jim Grosbach
d9ad52adff revert so I can get the right PR# in the log message.
llvm-svn: 108727
2010-07-19 17:19:40 +00:00
Jim Grosbach
c685756cfb Since ARM emits inline jump tables as part of the ConstantIsland pass,
it should set the jump table encloding the EK_Inline. This prevents
a second, unused, copy of the table from being emitted after the function
body. PR7499.

llvm-svn: 108722
2010-07-19 17:18:28 +00:00
Jim Grosbach
b97e2bbe32 Add combiner patterns to more effectively utilize the BFI (bitfield insert)
instruction for non-constant operands. This includes the case referenced
in the README.txt regarding a bitfield copy.

llvm-svn: 108608
2010-07-17 03:30:54 +00:00
Jim Grosbach
6e3b5fa91c add BFI to getTargetNodeName()
llvm-svn: 108603
2010-07-17 01:50:57 +00:00
Jim Grosbach
adc81f8ee8 Fix logic think-o
llvm-svn: 108601
2010-07-17 01:22:19 +00:00
Jim Grosbach
11013eda5a Add basic support to code-gen the ARM/Thumb2 bit-field insert (BFI) instruction
and a combine pattern to use it for setting a bit-field to a constant
value. More to come for non-constant stores.

llvm-svn: 108570
2010-07-16 23:05:05 +00:00
Evan Cheng
55f0c6b9fc Split -enable-finite-only-fp-math to two options:
-enable-no-nans-fp-math and -enable-no-infs-fp-math. All of the current codegen fp math optimizations only care whether the fp arithmetics arguments and results can never be NaN.

llvm-svn: 108465
2010-07-15 22:07:12 +00:00
Bob Wilson
bad47f62f6 Add support for NEON VMVN immediate instructions.
llvm-svn: 108324
2010-07-14 06:31:50 +00:00
Bob Wilson
103a0dcfe1 Add an ARM-specific DAG combining to avoid redundant VDUPLANE nodes.
Radar 7373643.

llvm-svn: 108303
2010-07-14 01:22:12 +00:00
Bob Wilson
a3f1901531 Use a target-specific VMOVIMM DAG node instead of BUILD_VECTOR to represent
NEON VMOV-immediate instructions.  This simplifies some things.

llvm-svn: 108275
2010-07-13 21:16:48 +00:00
Evan Cheng
0cc4ad983d Extend the r107852 optimization which turns some fp compare to code sequence using only i32 operations. It now optimize some f64 compares when fp compare is exceptionally slow (e.g. cortex-a8). It also catches comparison against 0.0.
llvm-svn: 108258
2010-07-13 19:27:42 +00:00
Bob Wilson
c1c6f4796e Move NEON "modified immediate" encode/decode into ARMAddressingModes.h to
avoid replicated code.

llvm-svn: 108227
2010-07-13 04:44:34 +00:00
Bob Wilson
8a2bdc8231 Remove some code that doesn't appear to do anything. All the ARM call
instructions already have implicit defs of LR.  The comment suggests that
this is intended to fix something like pr6111, but it doesn't really do
that either.

llvm-svn: 108186
2010-07-12 20:22:45 +00:00
Rafael Espindola
a76eccf815 Fix va_arg for doubles. With this patch VAARG nodes always contain the
correct alignment information, which simplifies ExpandRes_VAARG a bit.

The patch introduces a new alignment information to TargetLoweringInfo. This is
needed since the two natural candidates cannot be used:

* The 's' in target data: If this is set to the minimal alignment of any
  argument, getCallFrameTypeAlignment would return 4 for doubles on ARM for
  example.
* The getTransientStackAlignment method. It is possible for an architecture to
  have argument less aligned than what we maintain the stack pointer.

llvm-svn: 108072
2010-07-11 04:01:49 +00:00
Evan Cheng
0f54854a1d Check for FiniteOnlyFPMath as well.
llvm-svn: 107904
2010-07-08 20:12:24 +00:00
Evan Cheng
be1f7a931e r107852 is only safe with -enable-unsafe-fp-math to account for +0.0 == -0.0.
llvm-svn: 107856
2010-07-08 06:01:49 +00:00