13 Commits

Author SHA1 Message Date
Fangrui Song
6ae7b735db [ARM][test] Improve stack-protector tests
llvm/test/LTO/ARM/ssp-static-reloc.ll is more about using the static
relocation model with "PIC Level" and unrelated to the LTO infrastructure.
Move the test. Update stack_guard_remat.ll to clearly test "PIC Level"
with the relevant relocation models.
2023-10-31 15:30:08 -07:00
Fangrui Song
e018cbf720 [IR] Make stack protector symbol dso_local according to -f[no-]direct-access-external-data
There are two motivations.

`-fno-pic -fstack-protector -mstack-protector-guard=global` created
`__stack_chk_guard` is referenced directly on all ELF OSes except FreeBSD.
This patch allows referencing the symbol indirectly with
-fno-direct-access-external-data.

Some Linux kernel folks want
`-fno-pic -fstack-protector -mstack-protector-guard-reg=gs -mstack-protector-guard-symbol=__stack_chk_guard`
created `__stack_chk_guard` to be referenced directly, avoiding
R_X86_64_REX_GOTPCRELX (even if the relocation may be optimized out by the linker).
https://github.com/llvm/llvm-project/issues/60116
Why they need this isn't so clear to me.

---

Add module flag "direct-access-external-data" and set the dso_local property of
the stack protector symbol. The module flag can benefit other LLVMCodeGen
synthesized symbols that are not represented in LLVM IR.

Nowadays, with `-fno-pic` being uncommon, ideally we should set
"direct-access-external-data" when it is true. However, doing so would require
~90 clang/test tests to be updated, which are too much.

As a compromise, we set "direct-access-external-data" only when it's different
from the implied default value.

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D150841
2023-05-23 09:49:57 -07:00
Nikita Popov
bed1c7f061 [ARM] Convert some tests to opaque pointers (NFC) 2022-12-19 12:45:35 +01:00
Jay Foad
f510045d82 [CodeGen] Remove unneeded regex escaping in FileCheck patterns. NFC.
Take advantage of D117117 to simplify all {{\[}} to [ and {{\]}} to ].

Differential Revision: https://reviews.llvm.org/D117298
2022-02-18 16:10:56 +00:00
serge-sans-paille
4ab3041acb Revert "[NFC] remove explicit default value for strboolattr attribute in tests"
This reverts commit bda6e5bee04c75b1f1332b4fd1ac4e8ef6c3c247.

See https://lab.llvm.org/buildbot/#/builders/109/builds/15424 for instance
2021-05-24 19:43:40 +02:00
serge-sans-paille
bda6e5bee0 [NFC] remove explicit default value for strboolattr attribute in tests
Since d6de1e1a71406c75a4ea4d5a2fe84289f07ea3a1, no attributes is quivalent to
setting attribute to false.

This is a preliminary commit for https://reviews.llvm.org/D99080
2021-05-24 19:31:04 +02:00
Fangrui Song
502a77f125 Migrate function attribute "no-frame-pointer-elim" to "frame-pointer"="all" as cleanups after D56351 2019-12-24 15:57:33 -08:00
Matt Arsenault
f10061ec70 Add address space mangling to lifetime intrinsics
In preparation for allowing allocas to have non-0 addrspace.

llvm-svn: 299876
2017-04-10 20:18:21 +00:00
David Blaikie
79e6c74981 [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
2015-02-27 19:29:02 +00:00
Tim Northover
2ac7e4b3ee ARM: correctly expand LDR-lit based globals.
Quite a major error here: the expansions for the Pseudos with and without
folded load were mixed up. Fortunately it only affects ARM-mode, when not using
movw/movt, on Darwin. I'm guessing no-one actually uses that combination.

llvm-svn: 223986
2014-12-10 23:40:50 +00:00
Akira Hatanaka
2ee0e9e6ee [ARM, stack protector] If supported, use armv7 instructions.
This commit enables using movt/movw to load the stack guard address:

movw r0, :lower16:(L_g3$non_lazy_ptr-(LPC0_0+8))
movt r0, :upper16:(L_g3$non_lazy_ptr-(LPC0_0+8))
ldr r0, [pc, r0]

Previously a pc-relative load was emitted:

ldr r0, LCPI0_0
ldr r0, [pc, r0]

rdar://problem/18740489

llvm-svn: 220470
2014-10-23 04:17:05 +00:00
Akira Hatanaka
dc08c30df9 [ARM] In dynamic-no-pic mode, ARM's post-RA pseudo expansion was incorrectly
expanding pseudo LOAD_STATCK_GUARD using instructions that are normally used
in pic mode. This patch fixes the bug.

<rdar://problem/17886592>

llvm-svn: 214614
2014-08-02 05:40:40 +00:00
Akira Hatanaka
e5b6e0d231 [stack protector] Fix a potential security bug in stack protector where the
address of the stack guard was being spilled to the stack.

Previously the address of the stack guard would get spilled to the stack if it
was impossible to keep it in a register. This patch introduces a new target
independent node and pseudo instruction which gets expanded post-RA to a
sequence of instructions that load the stack guard value. Register allocator
can now just remat the value when it can't keep it in a register. 

<rdar://problem/12475629>

llvm-svn: 213967
2014-07-25 19:31:34 +00:00