Fix use-after-free bug in AffectedValueCallbackVH::allUsesReplacedWith
When transferring affected values in the cache from an old value,
identified by the value of the current callback, to the specified new
value we might need to insert a new entry into the DenseMap which
constitutes the cache. Doing so might delete the current callback
object. Move the copying logic into a new function, a member of the
assumption cache itself, so that we don't run into UB should the
callback handle itself be removed mid-copy.
Differential Revision: https://reviews.llvm.org/D28749
This should fix crashes when building lld (as part of the llvmXY ports).
Reported by: jbeich
PR: 216117
Add some shortcuts in LazyValueInfo to reduce compile time of
Correlated Value Propagation.
The patch is to partially fix PR10584. Correlated Value Propagation
queries LVI to check non-null for pointer params of each callsite. If
we know the def of param is an alloca instruction, we know it is
non-null and can return early from LVI. Similarly, CVP queries LVI to
check whether pointer for each mem access is constant. If the def of
the pointer is an alloca instruction, we know it is not a constant
pointer. These shortcuts can reduce the cost of CVP significantly.
Differential Revision: https://reviews.llvm.org/D18066
This significantly reduces memory usage and compilation time when
compiling a particular C++ source file of the graphics/colmap port.
PR: 215136
MFC after: 3 days
[PowerPC] Refactor soft-float support, and enable PPC64 soft float
This change enables soft-float for PowerPC64, and also makes
soft-float disable all vector instruction sets for both 32-bit and
64-bit modes. This latter part is necessary because the PPC backend
canonicalizes many Altivec vector types to floating-point types, and
so soft-float breaks scalarization support for many operations. Both
for embedded targets and for operating-system kernels desiring
soft-float support, it seems reasonable that disabling hardware
floating-point also disables vector instructions (embedded targets
without hardware floating point support are unlikely to have Altivec,
etc. and operating system kernels desiring not to use floating-point
registers to lower syscall cost are unlikely to want to use vector
registers either). If someone needs this to work, we'll need to
change the fact that we promote many Altivec operations to act on
v4f32. To make it possible to disable Altivec when soft-float is
enabled, hardware floating-point support needs to be expressed as a
positive feature, like the others, and not a negative feature,
because target features cannot have dependencies on the disabling of
some other feature. So +soft-float has now become -hard-float.
Fixes PR26970.
Pull in r283061 from upstream clang trunk (by Hal Finkel):
[PowerPC] Enable soft-float for PPC64, and +soft-float -> -hard-float
Enable soft-float support on PPC64, as the backend now supports it.
Also, the backend now uses -hard-float instead of +soft-float, so set
the target features accordingly.
Fixes PR26970.
Reported by: Mark Millard
PR: 214433
[PPC] Set SP after loading data from stack frame, if no red zone is
present
Follow-up to r280705: Make sure that the SP is only restored after
all data is loaded from the stack frame, if there is no red zone.
This completes the fix for
https://llvm.org/bugs/show_bug.cgi?id=26519.
Differential Revision: https://reviews.llvm.org/D24466
Reported by: Mark Millard
PR: 214433
Call Frame Optimization on i386 and libunwind, by disallowing the
optimization for i386-freebsd12.
This should fix some instances of broken exception handling when frame
pointers are omitted, in particular some unittests run during the build
of editors/libreoffice.
This hack will be removed as soon as upstream has implemented a more
permanent fix for this problem.
Upstream PR: https://llvm.org/bugs/show_bug.cgi?id=30879
Reviewed by: emaste
PR: 212343
[x86] don't try to create a vector integer inst for an SSE1 target
(PR30512)
This bug was introduced with:
http://reviews.llvm.org/rL272511
We need to restrict the lowering to v4f32 comparisons because that's
all SSE1 can handle.
This should fix:
https://llvm.org/bugs/show_bug.cgi?id=28044
This avoids a "Do not know how to custom type legalize this operation"
error when building the multimedia/ffmpeg port on i386 with SSE enabled.
[PPC] Claim stack frame before storing into it, if no red zone is
present
Unlike PPC64, PPC32/SVRV4 does not have red zone. In the absence of
it there is no guarantee that this part of the stack will not be
modified by any interrupt. To avoid this, make sure to claim the
stack frame first before storing into it.
This fixes https://llvm.org/bugs/show_bug.cgi?id=26519.
Differential Revision: https://reviews.llvm.org/D24093
Add ISD::EH_DWARF_CFA, simplify @llvm.eh.dwarf.cfa on Mips, fix on
PowerPC
LLVM has an @llvm.eh.dwarf.cfa intrinsic, used to lower the
GCC-compatible __builtin_dwarf_cfa() builtin. As pointed out in
PR26761, this is currently broken on PowerPC (and likely on ARM as
well). Currently, @llvm.eh.dwarf.cfa is lowered using:
ADD(FRAMEADDR, FRAME_TO_ARGS_OFFSET)
where FRAME_TO_ARGS_OFFSET defaults to the constant zero. On x86,
FRAME_TO_ARGS_OFFSET is lowered to 2*SlotSize. This setup, however,
does not work for PowerPC. Because of the way that the stack layout
works, the canonical frame address is not exactly (FRAMEADDR +
FRAME_TO_ARGS_OFFSET) on PowerPC (there is a lower save-area offset
as well), so it is not just a matter of implementing
FRAME_TO_ARGS_OFFSET for PowerPC (unless we redefine its semantics --
We can do that, since it is currently used only for
@llvm.eh.dwarf.cfa lowering, but the better to directly lower the CFA
construct itself (since it can be easily represented as a
fixed-offset FrameIndex)). Mips currently does this, but by using a
custom lowering for ADD that specifically recognizes the (FRAMEADDR,
FRAME_TO_ARGS_OFFSET) pattern.
This change introduces a ISD::EH_DWARF_CFA node, which by default
expands using the existing logic, but can be directly lowered by the
target. Mips is updated to use this method (which simplifies its
implementation, and I suspect makes it more robust), and updates
PowerPC to do the same.
Fixes PR26761.
Differential Revision: https://reviews.llvm.org/D24038
[PowerPC] Don't spill the frame pointer twice
When a function contains something, such as inline asm, which
explicitly clobbers the register used as the frame pointer, don't
spill it twice. If we need a frame pointer, it will be saved/restored
in the prologue/epilogue code. Explicitly spilling it again will
reuse the same spill slot used by the prologue/epilogue code, thus
clobbering the saved value. The same applies to the base-pointer or
PIC-base register.
Partially fixes PR26856. Thanks to Ulrich for his analysis and the
small inline-asm reproducer.
[PowerPC] Add support for -mlongcall
The "long call" option forces the use of the indirect calling
sequence for all calls (even those that don't really need it). GCC
provides this option; This is helpful, under certain circumstances,
for building very-large binaries, and some other specialized use
cases.
Fixes PR19098.
Pull in r280041 from upstream clang trunk (by Hal Finkel):
[PowerPC] Add support for -mlongcall
Add support for GCC's PowerPC -mlongcall option; the backend supports
the corresponding target feature as of r280040.
Fixes PR19098.
Don't reduce the width of vector mul if the target doesn't support
SSE2.
The patch is to fix PR30298, which is caused by rL272694. The
solution is to bail out if the target has no SSE2.
Differential Revision: https://reviews.llvm.org/D24288
This fixes building the multimedia/libx264 port on i386.
[AArch64] Return the correct size for TLSDESC_CALLSEQ
The branch relaxation pass is computing the wrong offsets because it assumes
TLSDESC_CALLSEQ eats up 4 bytes, when in fact it is lowered to an instruction
sequence taking up 16 bytes. This can become a problem in huge files with lots
of TLS accesses, as it may slowly move branch targets out of the range computed
by the branch relaxation pass.
Fixes PR24234 https://llvm.org/bugs/show_bug.cgi?id=24234
Differential Revision: https://reviews.llvm.org/D22870
This fixes "error in backend: fixup value out of range" when compiling
the misc/talkfilters port for AArch64.
Reported by: sbruno
PR: 201762
MFC after: 3 days
Fix for pr24346: arm asm label calculation error in sub
Some ARM instructions encode 32-bit immediates as a 8-bit integer
(0-255) and a 4-bit rotation (0-30, even) in its least significant 12
bits. The original fixup, FK_Data_4, patches the instruction by the
value bit-to-bit, regardless of the encoding. For example, assuming
the label L1 and L2 are 0x0 and 0x104 respectively, the following
instruction:
add r0, r0, #(L2 - L1) ; expects 0x104, i.e., 260
would be assembled to the following, which adds 1 to r0, instead of
260:
e2800104 add r0, r0, #4, 2 ; equivalently 1
The new fixup kind fixup_arm_mod_imm takes care of the encoding:
e2800f41 add r0, r0, #260
Patch by Ting-Yuan Huang!
This fixes label calculation for ARM assembly, and is needed to enable
ARM assembly sources for OpenSSL.
Requested by: jkim
MFC after: 3 days
[X86] AMD Bobcat CPU (btver1) doesn't support XSAVE
btver1 is a SSSE3/SSE4a only CPU - it doesn't have AVX and doesn't
support XSAVE.
Differential Revision: http://reviews.llvm.org/D17682
Pull in r262782 from upstream llvm trunk (by Simon Pilgrim):
[X86] AMD Bobcat CPU (btver1) doesn't support XSAVE
btver1 is a SSSE3/SSE4a only CPU - it doesn't have AVX and doesn't
support XSAVE.
Differential Revision: http://reviews.llvm.org/D17683
This ensures clang does not emit AVX instructions for CPUTYPE=btver1.
Reported by: Michel Depeige <demik+freebsd@lostwave.net>
PR: 211864
MFC after: 3 days
Only attempt to detect AVG if SSE2 is available
Summary:
In PR29973 Sanjay Patel reported an assertion failure when a certain
loop was optimized, for a target without SSE2 support. It turned out
this was because of the AVG pattern detection introduced in rL253952.
Prevent the assertion failure by bailing out early in
`detectAVGPattern()`, if the target does not support SSE2.
Also add a minimized test case.
Reviewers: congh, eli.friedman, spatel
Subscribers: emaste, llvm-commits
Differential Revision: http://reviews.llvm.org/D20905
This should fix assertion failures ("Requires at least SSE2!") when
building the games/0ad port with CPUTYPE=pentium3.
Reported by: madpilot
[VectorUtils] Fix nasty use-after-free
In truncateToMinimalBitwidths() we were RAUW'ing an instruction then
erasing it. However, that intruction could be cached in the map we're
iterating over. The first check is "I->use_empty()" which in most
cases would return true, as the (deleted) object was RAUW'd first so
would have zero use count. However in some cases the object could
have been polluted or written over and this wouldn't be the case.
Also it makes valgrind, asan and traditionalists who don't like their
compiler to crash sad.
No testcase as there are no externally visible symptoms apart from a
crash if the stars align.
Fixes PR26509.
This should fix crashes when building a number of ports on arm64.
Reported by: andrew
[X86] Emit a proper ADJCALLSTACKDOWN in EmitLoweredTLSAddr
We forgot to add the second machine operand to our ADJCALLSTACKDOWN,
resulting in crashes in PEI.
This fixes PR27071.
This should fix an assertion failure during buildworld, when using -Os,
and targeting either i386 directly, or building the 32-bit libraries on
amd64.
Reported by: Eric Camachat <eric.camachat@gmail.com>
the safe point to insert the prologue and epilogue of the function) on
X86. This prevents problems with some functions using TLS, such as in
jemalloc, and which was the cause for Address Sanitizer crashes. The
correct fix is still being discussed upstream.
[DwarfDebug] Move MergeValues to .cpp, NFC
Pull in r257979 from upstream llvm trunk, by Keno Fischer:
[DwarfDebug] Don't merge DebugLocEntries if their pieces overlap
Summary:
Later in DWARF emission we check that DebugLocEntries have
non-overlapping pieces, so we should create any such entries
by merging here.
Fixes PR26163.
Reviewers: aprantl
Differential Revision: http://reviews.llvm.org/D16249
Again, these will be merged to the official release_38 branch soon, but
we need them ASAP.
be merged to the official release_38 branch soon, but we need it ASAP):
Stop increasing alignment of externally-visible globals on ELF
platforms.
With ELF, the alignment of a global variable in a shared library will
get copied into an executables linked against it, if the executable even
accesss the variable. So, it's not possible to implicitly increase
alignment based on access patterns, or you'll break existing binaries.
This happened to affect libc++'s std::cout symbol, for example. See
thread: http://thread.gmane.org/gmane.comp.compilers.clang.devel/45311
(This is a re-commit of r257719, without the bug reported in
PR26144. I've tweaked the code to not assert-fail in
enforceKnownAlignment when computeKnownBits doesn't recurse far enough
to find the underlying Alloca/GlobalObject value.)
Differential Revision: http://reviews.llvm.org/D16145
