There is not an official documented ABI for frame pointers in Thumb2,
but we should try to emit something which is useful.
We use r7 as the frame pointer for Thumb code, which currently means
that if a function needs to save a high register (r8-r11), it will get
pushed to the stack between the frame pointer (r7) and link register
(r14). This means that while a stack unwinder can follow the chain of
frame pointers up the stack, it cannot know the offset to lr, so does
not know which functions correspond to the stack frames.
To fix this, we need to push the callee-saved registers in two batches,
with the first push saving the low registers, fp and lr, and the second
push saving the high registers. This is already implemented, but
previously only used for iOS. This patch turns it on for all Thumb2
targets when frame pointers are required by the ABI, and the frame
pointer is r7 (Windows uses r11, so this isn't a problem there). If
frame pointer elimination is enabled we still emit a single push/pop
even if we need a frame pointer for other reasons, to avoid increasing
code size.
We must also ensure that lr is pushed to the stack when using a frame
pointer, so that we end up with a complete frame record. Situations that
could cause this were rare, because we already push lr in most
situations so that we can return using the pop instruction.
Differential Revision: https://reviews.llvm.org/D23516
llvm-svn: 279506
Summary:
Currently fast-isel-abort will only abort for regular instructions,
and just warn for function calls, terminators, function arguments.
There is already fast-isel-abort-args but nothing for calls and
terminators.
This change turns the fast-isel-abort options into an integer option,
so that multiple levels of strictness can be defined.
This will help no being surprised when the "abort" option indeed does
not abort, and enables the possibility to write test that verifies
that no intrinsics are forgotten by fast-isel.
Reviewers: resistor, echristo
Subscribers: jfb, llvm-commits
Differential Revision: http://reviews.llvm.org/D7941
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 230775
The ARM backend has been using most of the MachO related subtarget
checks almost interchangeably, and since the only target it's had to
run on has been IOS (which is all three of MachO, Darwin and IOS) it's
worked out OK so far.
But we'd like to support embedded targets under the "*-*-none-macho"
triple, which means everything starts falling apart and inconsistent
behaviours emerge.
This patch should pick a reasonably sensible set of behaviours for the
new triple (and any others that come along, with luck). Some choices
were debatable (notably FP == r7 or r11), but we can revisit those
later when deficiencies become apparent.
llvm-svn: 198617
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
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.
llvm-svn: 183966
FastISel was only enabled for iOS ARM and Thumb2, this patch enables it
for ARM (not Thumb2) on Linux and NaCl.
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 test-suite on A15 hardware with --optimize-option=-O0 and
all the tests pass.
llvm-svn: 182877
Oliver Stannard