This commit creates a dummy LLVM IR function with one basic block and an unreachable
instruction for each parsed machine function when the MIR file doesn't have LLVM IR.
This change is required as the machine function analysis pass creates machine
functions only for the functions that are defined in the current LLVM module.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10135
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239778 91177308-0d34-0410-b5e6-96231b3b80d8
This commit reports an error when the MIR parser encounters a machine
function with the name that is the same as the name of a different
machine function.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10130
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239774 91177308-0d34-0410-b5e6-96231b3b80d8
constants in commented-out part of LLVMAttribute enum. Add tests that verify
that the safestack attribute is only allowed as a function attribute.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239772 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds the safe stack instrumentation pass to LLVM, which separates
the program stack into a safe stack, which stores return addresses, register
spills, and local variables that are statically verified to be accessed
in a safe way, and the unsafe stack, which stores everything else. Such
separation makes it much harder for an attacker to corrupt objects on the
safe stack, including function pointers stored in spilled registers and
return addresses. You can find more information about the safe stack, as
well as other parts of or control-flow hijack protection technique in our
OSDI paper on code-pointer integrity (http://dslab.epfl.ch/pubs/cpi.pdf)
and our project website (http://levee.epfl.ch).
The overhead of our implementation of the safe stack is very close to zero
(0.01% on the Phoronix benchmarks). This is lower than the overhead of
stack cookies, which are supported by LLVM and are commonly used today,
yet the security guarantees of the safe stack are strictly stronger than
stack cookies. In some cases, the safe stack improves performance due to
better cache locality.
Our current implementation of the safe stack is stable and robust, we
used it to recompile multiple projects on Linux including Chromium, and
we also recompiled the entire FreeBSD user-space system and more than 100
packages. We ran unit tests on the FreeBSD system and many of the packages
and observed no errors caused by the safe stack. The safe stack is also fully
binary compatible with non-instrumented code and can be applied to parts of
a program selectively.
This patch is our implementation of the safe stack on top of LLVM. The
patches make the following changes:
- Add the safestack function attribute, similar to the ssp, sspstrong and
sspreq attributes.
- Add the SafeStack instrumentation pass that applies the safe stack to all
functions that have the safestack attribute. This pass moves all unsafe local
variables to the unsafe stack with a separate stack pointer, whereas all
safe variables remain on the regular stack that is managed by LLVM as usual.
- Invoke the pass as the last stage before code generation (at the same time
the existing cookie-based stack protector pass is invoked).
- Add unit tests for the safe stack.
Original patch by Volodymyr Kuznetsov and others at the Dependable Systems
Lab at EPFL; updates and upstreaming by myself.
Differential Revision: http://reviews.llvm.org/D6094
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239761 91177308-0d34-0410-b5e6-96231b3b80d8
This commit connects the machine function analysis pass (which creates machine
functions) to the MIR parser, which will initialize the machine functions
with the state from the MIR file and reconstruct the machine IR.
This commit introduces a new interface called 'MachineFunctionInitializer',
which can be used to provide custom initialization for the machine functions.
This commit also introduces a new diagnostic class called
'DiagnosticInfoMIRParser' which is used for MIR parsing errors.
This commit modifies the default diagnostic handling in LLVMContext - now the
the diagnostics are printed directly into llvm::errs() so that the MIR parsing
errors can be printed with colours.
Reviewers: Justin Bogner
Differential Revision: http://reviews.llvm.org/D9928
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239753 91177308-0d34-0410-b5e6-96231b3b80d8
LLVM targeting aarch64 doesn't correctly produce aligned accesses for non-aligned
data at -O0/fast-isel (-mno-unaligned-access).
The root cause seems to be in fast-isel not producing unaligned access correctly
for -mno-unaligned-access.
The patch just aborts fast-isel for loads and stores when -mno-unaligned-access is
present.
The regression test is updated to check this new test case (-mno-unaligned-access
together with fast-isel).
Differential Revision: http://reviews.llvm.org/D10360
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239732 91177308-0d34-0410-b5e6-96231b3b80d8
The plugin now save the bitcode before and after optimizations and the
.o that is passed to the linker.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239726 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
ValueTracking used to overwrite the analysis results computed from
assumes and dominating conditions. This patch fixes this issue.
Test Plan: test/Analysis/ValueTracking/assume.ll
Reviewers: hfinkel, majnemer
Reviewed By: majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10283
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239718 91177308-0d34-0410-b5e6-96231b3b80d8
Re-commit after adding "-aarch64-neon-syntax=generic" to fix the failure on OS X.
This patch was firstly committed in r239514, then reverted in r239544 because of a syntax incompatible failure on OS X.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239711 91177308-0d34-0410-b5e6-96231b3b80d8
ARMTargetParser::getFPUFeatures should disable fp16 whenever it
disables vfp4, as otherwise something like -mcpu=cortex-a7 -mfpu=none
leaves us with fp16 enabled (though the only effect that will have is
a wrong build attribute).
Differential Revision: http://reviews.llvm.org/D10397
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239599 91177308-0d34-0410-b5e6-96231b3b80d8
It is valid for globals to be unnamed, but aliases must have a name. To avoid
creating invalid IR, we need to assign names to any aliases we create that
point to unnamed objects that have been moved into combined globals.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239590 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
A side effect of this change is that it IRBuilder now automatically
created debug info locations for new instructions, which is the
same as debug location of insertion point. This is fine for the
functions in questions (GetStoreValueForLoad and
GetMemInstValueForLoad), as they are used in two situations:
* GVN::processLoad, which tries to eliminate a load. In this case
new instructions would have the same debug location as the load they
eventually replace;
* MaterializeAdjustedValue, which adds new instructions to the end
of the basic blocks, which could later be used to replace the load
definition. In this case we don't yet know the way the load would
be eventually replaced (either by assembling the precomputed values
via PHI, or by using them directly), so just using the basic block
strategy seems to be reasonable. There is also a special case
in the code that *would* adjust the location of the last
instruction replacing the load definition to the location of the
load.
Test Plan: regression test suite
Reviewers: echristo, dberlin, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10405
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239585 91177308-0d34-0410-b5e6-96231b3b80d8
We were putting them in the filter field, which is correct for 64-bit
but wrong for 32-bit.
Also switch the order of scope table entry emission so outermost entries
are emitted first, and fix an obvious state assignment bug.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239574 91177308-0d34-0410-b5e6-96231b3b80d8
This intrinsic is like framerecover plus a load. It recovers the EH
registration stack allocation from the parent frame and loads the
exception information field out of it, giving back a pointer to an
EXCEPTION_POINTERS struct. It's designed for clang to use in SEH filter
expressions instead of accessing the EXCEPTION_POINTERS parameter that
is available on x64.
This required a minor change to MC to allow defining a label variable to
another absolute framerecover label variable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239567 91177308-0d34-0410-b5e6-96231b3b80d8
We cannot prepend __imp_ in the IR mangler because a function reference may
be emitted unmangled in a constant initializer. The linker is expected to
resolve such references to thunks. This is covered by the new test case.
Strictly speaking we ought to emit two undefined symbols, one with __imp_ and
one without, as we cannot know which symbol the final object file will refer
to. However, this would require rather intrusive changes to IRObjectFile,
and lld works fine without it for now.
This reimplements r239437, which was reverted in r239502.
Differential Revision: http://reviews.llvm.org/D10400
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239560 91177308-0d34-0410-b5e6-96231b3b80d8
This improves debug locations in passes that do a lot of basic block
transformations. Important case is LoopUnroll pass, the test for correct
debug locations accompanies this change.
Test Plan: regression test suite
Reviewers: dblaikie, sanjoy
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10367
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239551 91177308-0d34-0410-b5e6-96231b3b80d8
Revert "[AArch64] Match interleaved memory accesses into ldN/stN instructions."
Revert "Fixing MSVC 2013 build error."
The test/CodeGen/AArch64/aarch64-interleaved-accesses.ll test was failing on OS X.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239544 91177308-0d34-0410-b5e6-96231b3b80d8
This only updates one of the uses. The other is used in cases
that may never touch memory, so I'm not sure why this is even
calling it. Perhaps there should be a new, similar hook for such
cases or pass -1 for unknown address space.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239540 91177308-0d34-0410-b5e6-96231b3b80d8
Now actually stores the non-zero constant instead of 0.
I somehow forgot to include this part of r238108.
The test change was just an independent instruction order swap,
so just add another check line to satisfy CHECK-NEXT.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239539 91177308-0d34-0410-b5e6-96231b3b80d8
Flat instructions don't exist on SI, but there is a bug in the backend that
allows them to be selected.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239533 91177308-0d34-0410-b5e6-96231b3b80d8
This patch ensures that SHL/SRL/SRA shifts for i8 and i16 vectors avoid scalarization. It builds on the existing i8 SHL vectorized implementation of moving the shift bits up to the sign bit position and separating the 4, 2 & 1 bit shifts with several improvements:
1 - SSE41 targets can use (v)pblendvb directly with the sign bit instead of performing a comparison to feed into a VSELECT node.
2 - pre-SSE41 targets were masking + comparing with an 0x80 constant - we avoid this by using the fact that a set sign bit means a negative integer which can be compared against zero to then feed into VSELECT, avoiding the need for a constant mask (zero generation is much cheaper).
3 - SRA i8 needs to be unpacked to the upper byte of a i16 so that the i16 psraw instruction can be correctly used for sign extension - we have to do more work than for SHL/SRL but perf tests indicate that this is still beneficial.
The i16 implementation is similar but simpler than for i8 - we have to do 8, 4, 2 & 1 bit shifts but less shift masking is involved. SSE41 use of (v)pblendvb requires that the i16 shift amount is splatted to both bytes however.
Tested on SSE2, SSE41 and AVX machines.
Differential Revision: http://reviews.llvm.org/D9474
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239509 91177308-0d34-0410-b5e6-96231b3b80d8
