Commit Graph

12 Commits

Author SHA1 Message Date
Peter Collingbourne 78f1ecc59c ARM: When spilling extra registers for alignment, prefer low registers on all Thumb targets.
This makes it more likely that we can use the 16-bit push and pop instructions
on Thumb-2, saving around 4 bytes per function.

Differential Revision: http://reviews.llvm.org/D9165

llvm-svn: 235637
2015-04-23 20:31:26 +00:00
Reid Kleckner 2d9bb65b3d ARM / x86_64 varargs: Don't save regparms in prologue without va_start
There's no need to do this if the user doesn't call va_start. In the
future, we're going to have thunks that forward these register
parameters with musttail calls, and they won't need these spills for
handling va_start.

Most of the test suite changes are adding va_start calls to existing
tests to keep things working.

llvm-svn: 216294
2014-08-22 21:59:26 +00:00
Tim Northover b4ddc0845a ARM & AArch64: make use of common cmpxchg idioms after expansion
The C and C++ semantics for compare_exchange require it to return a bool
indicating success. This gets mapped to LLVM IR which follows each cmpxchg with
an icmp of the value loaded against the desired value.

When lowered to ldxr/stxr loops, this extra comparison is redundant: its
results are implicit in the control-flow of the function.

This commit makes two changes: it replaces that icmp with appropriate PHI
nodes, and then makes sure earlyCSE is called after expansion to actually make
use of the opportunities revealed.

I've also added -{arm,aarch64}-enable-atomic-tidy options, so that
existing fragile tests aren't perturbed too much by the change. Many
of them either rely on undef/unreachable too pervasively to be
restored to something well-defined (particularly while making sure
they test the same obscure assert from many years ago), or depend on a
particular CFG shape, which is disrupted by SimplifyCFG.

rdar://problem/16227836

llvm-svn: 209883
2014-05-30 10:09:59 +00:00
Stephen Lin d24ab20e9b Mass update to CodeGen tests to use CHECK-LABEL for labels corresponding to function definitions for more informative error messages. No functionality change and all updated tests passed locally.
This update was done with the following bash script:

  find test/CodeGen -name "*.ll" | \
  while read NAME; do
    echo "$NAME"
    if ! grep -q "^; *RUN: *llc.*debug" $NAME; then
      TEMP=`mktemp -t temp`
      cp $NAME $TEMP
      sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \
      while read FUNC; do
        sed -i '' "s/;\(.*\)\([A-Za-z0-9_-]*\):\( *\)$FUNC: *\$/;\1\2-LABEL:\3$FUNC:/g" $TEMP
      done
      sed -i '' "s/;\(.*\)-LABEL-LABEL:/;\1-LABEL:/" $TEMP
      sed -i '' "s/;\(.*\)-NEXT-LABEL:/;\1-NEXT:/" $TEMP
      sed -i '' "s/;\(.*\)-NOT-LABEL:/;\1-NOT:/" $TEMP
      sed -i '' "s/;\(.*\)-DAG-LABEL:/;\1-DAG:/" $TEMP
      mv $TEMP $NAME
    fi
  done

llvm-svn: 186280
2013-07-14 06:24:09 +00:00
Cameron Zwarich 338d362200 Roll r127459 back in:
Optimize trivial branches in CodeGenPrepare, which often get created from the
lowering of objectsize intrinsics. Unfortunately, a number of tests were relying
on llc not optimizing trivial branches, so I had to add an option to allow them
to continue to test what they originally tested.

This fixes <rdar://problem/8785296> and <rdar://problem/9112893>.

llvm-svn: 127498
2011-03-11 21:52:04 +00:00
Daniel Dunbar 94ccb27b43 Revert r127459, "Optimize trivial branches in CodeGenPrepare, which often get
created from the", it broke some GCC test suite tests.

llvm-svn: 127477
2011-03-11 19:30:30 +00:00
Cameron Zwarich cc27b3acc4 Optimize trivial branches in CodeGenPrepare, which often get created from the
lowering of objectsize intrinsics. Unfortunately, a number of tests were relying
on llc not optimizing trivial branches, so I had to add an option to allow them
to continue to test what they originally tested.

This fixes <rdar://problem/8785296> and <rdar://problem/9112893>.

llvm-svn: 127459
2011-03-11 04:54:27 +00:00
Evan Cheng eb56dca4fd Fix epilogue codegen to avoid leaving the stack pointer in an invalid
state. Previously Thumb2 would restore sp from fp like this:
mov sp, r7
sub, sp, #4
If an interrupt is taken after the 'mov' but before the 'sub', callee-saved
registers might be clobbered by the interrupt handler. Instead, try
restoring directly from sp:
add sp, #4
Or, if necessary (with VLA, etc.) use a scratch register to compute sp and
then restore it:
sub.w r4, r7, #8
mov sp, r7
rdar://8465407

llvm-svn: 119977
2010-11-22 18:12:04 +00:00
Rafael Espindola 5a24a56e1e Remove the arm_aapcscc marker from the tests. It is the default
for the linux targets.

llvm-svn: 106029
2010-06-15 19:04:29 +00:00
Evan Cheng b18525937c More consistent thumb1 asm printing.
llvm-svn: 89328
2009-11-19 06:57:41 +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 b972e5633f It turns out most of the thumb2 instructions are not allowed to touch SP. The semantics of such instructions are unpredictable. We have just been lucky that tests have been passing.
This patch takes pain to ensure all the PEI lowering code does the right thing when lowering frame indices, insert code to manipulate stack pointers, etc. It's also custom lowering dynamic stack alloc into pseudo instructions so we can insert the right instructions at scheduling time.

This fixes PR4659 and PR4682.

llvm-svn: 78361
2009-08-07 00:34:42 +00:00