Commit Graph

2 Commits

Author SHA1 Message Date
JF Bastien
fe532ad6d6 Enable FastISel on ARM for Linux and NaCl, not MCJIT
This is a resubmit of r182877, which was reverted because it broken
MCJIT tests on ARM. The patch leaves MCJIT on ARM as it was before: only
enabled for iOS. I've CC'ed people from the original review and revert.

FastISel was only enabled for iOS ARM and Thumb2, this patch enables it
for ARM (not Thumb2) on Linux and NaCl, but not MCJIT.

Thumb2 support needs a bit more work, mainly around register class
restrictions.

The patch punts to SelectionDAG when doing TLS relocation on non-Darwin
targets. I will fix this and other FastISel-to-SelectionDAG failures in
a separate patch.

The patch also forces FastISel to retain frame pointers: iOS always
keeps them for backtracking (so emitted code won't change because of
this), but Linux was getting much worse code that was incorrect when
using big frames (such as test-suite's lencod). I'll also fix this in a
later patch, it will probably require a peephole so that FastISel
doesn't rematerialize frame pointers back-to-back.

The test changes are straightforward, similar to:
  http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20130513/174279.html
They also add a vararg test that got dropped in that change.

I ran all of lnt test-suite on A15 hardware with --optimize-option=-O0
and all the tests pass. All the tests also pass on x86 make check-all. I
also re-ran the check-all tests that failed on ARM, and they all seem to
pass.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183966 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-14 02:49:43 +00:00
JF Bastien
8fc760cbe8 ARM FastISel integer sext/zext improvements
My recent ARM FastISel patch exposed this bug:
  http://llvm.org/bugs/show_bug.cgi?id=16178
The root cause is that it can't select integer sext/zext pre-ARMv6 and
asserts out.

The current integer sext/zext code doesn't handle other cases gracefully
either, so this patch makes it handle all sext and zext from i1/i8/i16
to i8/i16/i32, with and without ARMv6, both in Thumb and ARM mode. This
should fix the bug as well as make FastISel faster because it bails to
SelectionDAG less often. See fastisel-ext.patch for this.

fastisel-ext-tests.patch changes current tests to always use reg-imm AND
for 8-bit zext instead of UXTB. This simplifies code since it is
supported on ARMv4t and later, and at least on A15 both should perform
exactly the same (both have exec 1 uop 1, type I).

2013-05-31-char-shift-crash.ll is a bitcode version of the above bug
16178 repro.

fast-isel-ext.ll tests all sext/zext combinations that ARM FastISel
should now handle.

Note that my ARM FastISel enabling patch was reverted due to a separate
failure when dealing with MCJIT, I'll fix this second failure and then
turn FastISel on again for non-iOS ARM targets.

I've tested "make check-all" on my x86 box, and "lnt test-suite" on A15
hardware.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183551 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-07 20:10:37 +00:00