[LangRef] Disallow accessing byval arguments from tail-called functions (#110093)

We already disallow accessing the callee's allocas from a tail-called
function, because their stack memory will hav

[LangRef] Disallow accessing byval arguments from tail-called functions (#110093)

We already disallow accessing the callee's allocas from a tail-called
function, because their stack memory will have been de-allocated before
the tail call. I think this should apply to byval arguments too, as they
also occupy space in the caller's stack frame.

This was originally part of #109943, spilt out for separate review.

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Revert "[ARM] musttail fixes"
committed by accident, see #104795

This reverts commit a2088a24dad31ebe44c93751db17307fdbe1f0e2.

[ARM] musttail fixes

Backend:
- Caller and callee arguments no longer have to match, just to take up the same space, as they can be changed before the call
- Allowed tail calls if callee and callee

[ARM] musttail fixes

Backend:
- Caller and callee arguments no longer have to match, just to take up the same space, as they can be changed before the call
- Allowed tail calls if callee and callee both (or neither) use sret, wheras before it would be dissalowed if either used sret
- Allowed tail calls if byval args are used
- Added debug trace for IsEligibleForTailCallOptimisation

Frontend (clang):
- Do not generate extra alloca if sret is used with musttail, as the space for the sret is allocated already

Change-Id: Ic7f246a7eca43c06874922d642d7dc44bdfc98ec

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[ARM] Convert some tests to opaque pointers (NFC)

[ARM] implement LOAD_STACK_GUARD for remaining targets

Currently, LOAD_STACK_GUARD on ARM is only implemented for Mach-O targets, and
other targets rely on the generic support which may result in sp

[ARM] implement LOAD_STACK_GUARD for remaining targets

Currently, LOAD_STACK_GUARD on ARM is only implemented for Mach-O targets, and
other targets rely on the generic support which may result in spilling of the
stack canary value or address, or may cause it to be kept in a callee save
register across function calls, which means they essentially get spilled as
well, only by the callee when it wants to free up this register.

So let's implement LOAD_STACK GUARD for other targets as well. This ensures
that the load of the stack canary is rematerialized fully in the epilogue.

This code was split off from

D112768: [ARM] implement support for TLS register based stack protector

for which it is a prerequisite.

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D112811

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OpaquePtr: Bulk update tests to use typed byval

Upgrade of the IR text tests should be the only thing blocking making
typed byval mandatory. Partially done through regex and partially
manual.

ARM: stop emitting blx instructions for most calls on MachO.

I'm really not sure why we were in the first place, it's the linker's job to
convert between BL/BLX as necessary. Even worse, using BLX l

ARM: stop emitting blx instructions for most calls on MachO.

I'm really not sure why we were in the first place, it's the linker's job to
convert between BL/BLX as necessary. Even worse, using BLX left Thumb calls
that could be locally resolved completely unencodable since all offsets to BLX
are multiples of 4.

rdar://26182344

llvm-svn: 269101

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Use movw/movt instead of constant pool loads to lower byval parameter copies

Summary:
The ARM backend can use a loop to implement copying byval parameters before
a call. In non-thumb2 mode it uses a

Use movw/movt instead of constant pool loads to lower byval parameter copies

Summary:
The ARM backend can use a loop to implement copying byval parameters before
a call. In non-thumb2 mode it uses a constant pool load to materialize the
trip count. For targets that need movt instead (e.g. Native Client), use
the same code as in thumb2 mode to materialize the trip count.

Reviewers: jfb, t.p.northover

Differential Revision: http://reviews.llvm.org/D8442

llvm-svn: 233324

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[opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction

One of several parallel first steps to remove the target type of pointers,
replacing them with a

[opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction

One of several parallel first steps to remove the target type of pointers,
replacing them with a single opaque pointer type.

This adds an explicit type parameter to the gep instruction so that when the
first parameter becomes an opaque pointer type, the type to gep through is
still available to the instructions.

* This doesn't modify gep operators, only instructions (operators will be
handled separately)

* Textual IR changes only. Bitcode (including upgrade) and changing the
in-memory representation will be in separate changes.

* geps of vectors are transformed as:
getelementptr <4 x float*> %x, ...
->getelementptr float, <4 x float*> %x, ...
Then, once the opaque pointer type is introduced, this will ultimately look
like:
getelementptr float, <4 x ptr> %x
with the unambiguous interpretation that it is a vector of pointers to float.

* address spaces remain on the pointer, not the type:
getelementptr float addrspace(1)* %x
->getelementptr float, float addrspace(1)* %x
Then, eventually:
getelementptr float, ptr addrspace(1) %x

Importantly, the massive amount of test case churn has been automated by
same crappy python code. I had to manually update a few test cases that
wouldn't fit the script's model (r228970,r229196,r229197,r229198). The
python script just massages stdin and writes the result to stdout, I
then wrapped that in a shell script to handle replacing files, then
using the usual find+xargs to migrate all the files.

update.py:
import fileinput
import sys
import re

ibrep = re.compile(r"(^.*?[^%\w]getelementptr inbounds )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")
normrep = re.compile( r"(^.*?[^%\w]getelementptr )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")

def conv(match, line):
if not match:
return line
line = match.groups()[0]
if len(match.groups()[5]) == 0:
line += match.groups()[2]
line += match.groups()[3]
line += ", "
line += match.groups()[1]
line += "\n"
return line

for line in sys.stdin:
if line.find("getelementptr ") == line.find("getelementptr inbounds"):
if line.find("getelementptr inbounds") != line.find("getelementptr inbounds ("):
line = conv(re.match(ibrep, line), line)
elif line.find("getelementptr ") != line.find("getelementptr ("):
line = conv(re.match(normrep, line), line)
sys.stdout.write(line)

apply.sh:
for name in "$@"
do
python3 `dirname "$0"`/update.py < "$name" > "$name.tmp" && mv "$name.tmp" "$name"
rm -f "$name.tmp"
done

The actual commands:
From llvm/src:
find test/ -name *.ll | xargs ./apply.sh
From llvm/src/tools/clang:
find test/ -name *.mm -o -name *.m -o -name *.cpp -o -name *.c | xargs -I '{}' ../../apply.sh "{}"
From llvm/src/tools/polly:
find test/ -name *.ll | xargs ./apply.sh

After that, check-all (with llvm, clang, clang-tools-extra, lld,
compiler-rt, and polly all checked out).

The extra 'rm' in the apply.sh script is due to a few files in clang's test
suite using interesting unicode stuff that my python script was throwing
exceptions on. None of those files needed to be migrated, so it seemed
sufficient to ignore those cases.

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7636

llvm-svn: 230786

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Struct byval: fix a copy-paste error for thumb2.

PR17309

llvm-svn: 192730

Revert "Tests: Be less dependent on a specific schedule/regalloc"

This reverts r192454

Apparently FileCheck isn't as smart as I though and does not enforce a
topological order between variable defs

Revert "Tests: Be less dependent on a specific schedule/regalloc"

This reverts r192454

Apparently FileCheck isn't as smart as I though and does not enforce a
topological order between variable defs+uses.

llvm-svn: 192472

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Tests: Be less dependent on a specific schedule/regalloc

llvm-svn: 192454

Revert 189756 for now, it doesn't match what rdar://14871821 really wants.

What we really want is to enable Swift by default for *v7s triples (and there already seems to be some logic which attempts

Revert 189756 for now, it doesn't match what rdar://14871821 really wants.

What we really want is to enable Swift by default for *v7s triples (and there already seems to be some logic which attempts to do that). In that case the iOS version doesn't matter.

llvm-svn: 189763

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ARM: Default to Swift when compiling for iOS 6 or later.

Test cases adjusted accordingly.

This fixes rdar://14871821.

llvm-svn: 189756

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.

Th

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

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ARM: tail-call inside a function where part of a byval argument is on caller's
local frame causes problem.

For example:
void f(StructToPass s) {
g(&s, sizeof(s));
}
will cause problem with tail-ca

ARM: tail-call inside a function where part of a byval argument is on caller's
local frame causes problem.

For example:
void f(StructToPass s) {
g(&s, sizeof(s));
}
will cause problem with tail-call since part of s is passed via registers and
saved in f's local frame. When g tries to access s, part of s may be corrupted
since f's local frame is popped out before the tail-call.

The current fix is to disable tail-call if getVarArgsRegSaveSize is not 0 for
the caller. This is a conservative approach, if we can prove the address of
s or part of s is not taken and passed to g, it should be okay to perform
tail-call.

rdar://12442472

llvm-svn: 165853

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ARM: use NOEN loads and stores if possible when handling struct byval.

This change is to be enabled in clang.

rdar://9877866

llvm-svn: 158684

ARM: add testing case for struct byval

rdar://9877866

llvm-svn: 157876