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11 Commits

Author SHA1 Message Date
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
Jim Grosbach d7cf55cd0e Use Unified Assembly Syntax for the ARM backend. 
llvm-svn: 86494
 2009-11-09 00:11:35 +00:00
Bob Wilson 6dd3b9ad58 Convert some ARM tests with lots of greps to use FileCheck. 
llvm-svn: 83651
 2009-10-09 17:20:46 +00:00
Dan Gohman c8054d90fb Eliminate more uses of llvm-as and llvm-dis. 
llvm-svn: 81293
 2009-09-09 00:09:15 +00:00
Evan Cheng d76d0aa68a Move thumb and thumb2 tests into separate directories. 
llvm-svn: 74068
 2009-06-24 06:36:07 +00:00
Dan Gohman f9dd170e36 Convert tests using "| wc -l | grep ..." to use the count script. 
llvm-svn: 41097
 2007-08-15 13:36:28 +00:00
Reid Spencer b5dc70c270 For PR1319: Upgrade to use new test harness 
llvm-svn: 36076
 2007-04-15 19:11:47 +00:00
Evan Cheng fa6532a3b9 -march=arm -enable-thumb => -march=thumb 
llvm-svn: 34522
 2007-02-23 03:15:39 +00:00
Reid Spencer ce380568b5 For PR761: 
Remove "target endian/pointersize" or add "target datalayout" to make
the test parse properly or set the datalayout because defaults changes.

For PR645:
Make global names use the @ prefix.

For llvm-upgrade changes:
Fix test cases or completely remove use of llvm-upgrade for test cases
that cannot survive the new renaming or upgrade capabilities.

llvm-svn: 33533
 2007-01-26 08:25:06 +00:00
Evan Cheng a5007faaa6 ARM test cases contributed by Apple. 
llvm-svn: 33354
 2007-01-19 09:20:23 +00:00
Reid Spencer 83b3d82672 Regression is gone, don't try to find it on clean target. 
llvm-svn: 33296
 2007-01-17 07:59:14 +00:00