Commit Graph

15 Commits

Author SHA1 Message Date
Evan Cheng
529916ca4a Add some missing isel predicates on def : pat patterns to avoid generating VFP vmla / vmls (they cause stalls). Disabling them in isel is properly not a right solution, I'll look into a proper solution next.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118922 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-12 20:32:20 +00:00
Evan Cheng
8239daf7c8 Two sets of changes. Sorry they are intermingled.
1. Fix pre-ra scheduler so it doesn't try to push instructions above calls to
   "optimize for latency". Call instructions don't have the right latency and
   this is more likely to use introduce spills.
2. Fix if-converter cost function. For ARM, it should use instruction latencies,
   not # of micro-ops since multi-latency instructions is completely executed
   even when the predicate is false. Also, some instruction will be "slower"
   when they are predicated due to the register def becoming implicit input.
   rdar://8598427


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118135 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-03 00:45:17 +00:00
Jakob Stoklund Olesen
7eb589d3f9 Try again to disable critical edge splitting in CodeGenPrepare.
The bug that broke i386 linux has been fixed in r115191.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115204 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-30 20:51:52 +00:00
Owen Anderson
b20b85168c Part one of switching to using a more sane heuristic for determining if-conversion profitability.
Rather than having arbitrary cutoffs, actually try to cost model the conversion.

For now, the constants are tuned to more or less match our existing behavior, but these will be
changed to reflect realistic values as this work proceeds.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114973 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-28 18:32:13 +00:00
Jakob Stoklund Olesen
08342f2d11 Revert "Disable codegen prepare critical edge splitting. Machine instruction passes now"
This reverts revision 114633. It was breaking llvm-gcc-i386-linux-selfhost.

It seems there is a downstream bug that is exposed by
-cgp-critical-edge-splitting=0. When that bug is fixed, this patch can go back
in.

Note that the changes to tailcallfp2.ll are not reverted. They were good are
required.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114859 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-27 18:43:48 +00:00
Evan Cheng
dd3a41a6b3 Disable codegen prepare critical edge splitting. Machine instruction passes now
break critical edges on demand.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114633 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-23 06:55:34 +00:00
Jim Grosbach
e7c1416263 Now that register allocation properly considers reserved regs, simplify the
ARM register class allocation order functions to take advantage of that.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112841 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-02 18:14:29 +00:00
Bill Wendling
bb47d3b471 The optimize comparisons pass removes the "cmp" instruction this is checking for.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110739 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-10 22:16:05 +00:00
Evan Cheng
3144687df7 - 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%.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109279 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-23 22:39:59 +00:00
Evan Cheng
4a863e2c75 More register pressure aware scheduling work.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109064 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-21 23:53:58 +00:00
Bill Wendling
4b722108e2 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106693 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-23 23:00:16 +00:00
Rafael Espindola
1e81966626 Remove arm_apcscc from the test files. It is the default and doing this
matches what llvm-gcc and clang now produce.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106221 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-17 15:18:27 +00:00
Evan Cheng
046fa3f90a Fix some latency computation bugs: if the use is not a machine opcode do not just return zero.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105061 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-28 23:26:21 +00:00
Dan Gohman
f182b23f8f When canonicalizing icmp operand order to put the loop invariant
operand on the left, the interesting operand is on the right. This
fixes a bug where LSR was failing to recognize ICmpZero uses,
which led it to be unable to reverse the induction variable in the
attached testcase.

Delete test/CodeGen/X86/stack-color-with-reg-2.ll, because its test
is extremely fragile and hard to meaningfully update.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104262 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-20 19:26:52 +00:00
Dan Gohman
a2086b3483 Teach LSR how to cope better with unrolled loops on targets where
the addressing modes don't make this trivially easy. This allows
it to avoid falling into the less precise heuristics in more
cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104186 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-19 23:43:12 +00:00