Currently, if the assembler encounters an error after parsing (such as an
out-of-range fixup), it reports this as a fatal error, and so stops after the
first error. However, for most of these there is an obvious way to recover
after emitting the error, such as emitting the fixup with a value of zero. This
means that we can report on all of the errors in a file, not just the first
one. MCContext::reportError records the fact that an error was encountered, so
we won't actually emit an object file with the incorrect contents.
Differential Revision: http://reviews.llvm.org/D14717
llvm-svn: 253328
This adds reportError to MCContext, which can be used as an alternative to
reportFatalError when the assembler wants to try to continue processing the
rest of the file after the error is reported, so that all of the errors ina
file can be reported. It records the fact that an error was encountered, so we
can avoid emitting an object file if any errors occurred.
This patch doesn't add any uses of this function (a later patch will convert
most uses of reportFatalError to use it), but there is a small functional
change: we use the SourceManager to print the error message, even if we have a
null SMLoc. This means that we get a SourceManager-style message, with the file
and line information shown as <unknown>, rather than the "LLVM ERROR" style
used by report_fatal_error.
llvm-svn: 253327
The way prelink used to work was
* The compiler decides if a given section only has relocations that
are know to point to the same DSO. If so, it names it
.data.rel.ro.local<something>.
* The static linker puts all of these together.
* The prelinker program assigns addresses to each library and resolves
the local relocations.
There are many problems with this:
* It is incompatible with address space randomization.
* The information passed by the compiler is redundant. The linker
knows if a given relocation is in the same DSO or not. If could sort
by that if so desired.
* There are newer ways of speeding up DSO (gnu hash for example).
* Even if we want to implement this again in the compiler, the previous
implementation is pretty broken. It talks about relocations that are
"resolved by the static linker". If they are resolved, there are none
left for the prelinker. What one needs to track is if an expression
will require only dynamic relocations that point to the same DSO.
At this point it looks like the prelinker is an historical curiosity.
For example, fedora has retired it because it failed to build for two
releases
(http://pkgs.fedoraproject.org/cgit/prelink.git/commit/?id=eb43100a8331d91c801ee3dcdb0a0bb9babfdc1f)
This patch removes support for it. That is, it stops printing the
".local" sections.
llvm-svn: 253280
This was regressed in r252656 which wasn't quite NFC. Instead of using a
custom instruction as before, use a pattern to select CONST_I32 for the
global addrs.
Differential Revision: http://reviews.llvm.org/D14587
llvm-svn: 253276
Summary:
Previously return type information for a function was derived from
return dag nodes. But this didn't work for dags with != return node. So
instead compute it directly from the LLVM function as is done for imports.
Differential Revision: http://reviews.llvm.org/D14593
llvm-svn: 253251
Summary: This is to match the new version in the spec
Reviewers: sunfish
Subscribers: jfb, llvm-commits, dschuff
Differential Revision: http://reviews.llvm.org/D14519
llvm-svn: 253249
On top of that, don't bother allocating and initializing UnwindHelp if
we don't have any funclets. Currently we always use RBP as our frame
pointer when funclets are present, so this change makes it impossible to
come here without any fixed stack objects.
Fixes PR25533.
llvm-svn: 253245
We sometimes create intermediate subtract instructions during
reassociation. Adding these to the worklist to revisit exposes many
additional reassociation opportunities.
Patch by Aditya Nandakumar.
llvm-svn: 253240
We tried to move the insertion point beyond instructions like landingpad
and cleanuppad.
However, we *also* tried to move past catchpad. This is problematic
because catchpad is also a terminator.
This fixes PR25541.
llvm-svn: 253238
Storing the source location of the expression that created a constant pool
entry allows us to emit better error messages if we later discover that the
expression cannot be represented by a relocation.
Differential Revision: http://reviews.llvm.org/D14646
llvm-svn: 253220
The MCValue class can store a SMLoc to allow better error messages to be
emitted if an error is detected after parsing. The ARM and AArch64 assembly
parsers were not setting this, so error messages did not have source
information.
Differential Revision: http://reviews.llvm.org/D14645
llvm-svn: 253219
Summary:
* ARMv6KZ is the "canonical" name, given in the ARMARM
* ARMv6Z is an "official abbreviation" for it, mentioned in the ARMARM
* ARMv6ZK is a popular misspelling, which we should support as an alias.
The patch corrects the handling of the names.
Functional changes:
* ARMv6Z no longer treated as an architecture in its own right
* ARMv6ZK renamed to ARMv6KZ, accepting ARMv6ZK as an alias
* arm1176jz-s and arm1176jzf-s recognized as ARMv6ZK, instead of ARMv6K
* default ARMv6K CPU changed to arm1176j-s
Reviewers: rengolin, logan, compnerd
Subscribers: aemerson, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D14568
llvm-svn: 253206
This was left implicit and never ever checked, which means we could have a CMPZ against some non-zero value and we were carrying on with BFI conversion regardless.
Caught by Oliver Stannard using csmith; regression test added.
llvm-svn: 253195
Summary:
This fails a check in Verifier.cpp, which checks for location matches between the declared
variable and the !dbg attachments.
Reviewers: dnovillo, dblaikie, danielcdh
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14657
llvm-svn: 253194
The AArch64 assembler was silently ignoring instructions like this:
ldr foo, =bar
AArch64AsmParser::parseOperand was returning true as the parse failed, but was
not calling AArch64AsmParser::Error to report this to the user, so the
instruction was ignored without printing an error message.
Differential Revision: http://reviews.llvm.org/D14651
llvm-svn: 253193
Summary: Since we're passing references to dbg.value as pointers,
we need to have the frontend properly declare their sizes and
alignments (as it already does for regular pointers) in preparation
for my upcoming patch to have the verifer check that the sizes agree.
Also augment the backend logic that skips actually emitting this
information into DWARF such that it also handles reference types.
Reviewers: aprantl, dexonsmith, dblaikie
Subscribers: dblaikie, llvm-commits
Differential Revision: http://reviews.llvm.org/D14275
llvm-svn: 253186
Summary: Moving landingpads into successor basic blocks makes the
verifier sad. Teach Sink that much like PHI nodes and terminator
instructions, landingpads (and cleanuppads, etc.) may not be moved
between basic blocks.
Reviewers: majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14475
llvm-svn: 253182
Global to local demotion can speed up programs that use globals a lot. It is particularly useful with LTO, when the entire call graph is known and most functions have been internalized.
For a global to be demoted, it must only be accessed by one function and that function:
1. Must never recurse directly or indirectly, else the GV would be clobbered.
2. Must never rely on the value in GV at the start of the function (apart from the initializer).
GlobalOpt can already do this, but it is hamstrung and only ever tries to demote globals inside "main", because C++ gives extra guarantees about how main is called - once and only once.
In LTO mode, we can often prove the first property (if the function is internal by this point, we know enough about the callgraph to determine if it could possibly recurse). FunctionAttrs now infers the "norecurse" attribute for this reason.
The second property can be proven for a subset of functions by proving that all loads from GV are dominated by a store to GV. This is conservative in the name of compile time - this only requires a DominatorTree which is fairly cheap in the grand scheme of things. We could do more fancy stuff with MemoryDependenceAnalysis too to catch more cases but this appears to catch most of the useful ones in my testing.
llvm-svn: 253168
The current implementation of GEP visitor in InstCombine fails with assertion on Vector GEP with mix of scalar and vector types, like this:
getelementptr double, double* %a, <8 x i32> %i
(It fails to create a "sext" from <8 x i32> to <8 x i64>)
I fixed it and added some tests.
Differential Revision: http://reviews.llvm.org/D14485
llvm-svn: 253162
Summary:
Currently we always recompute LCSSA for outer loops after unrolling an
inner loop. That leads to compile time problem when we have big loop
nests, and we can solve it by avoiding unnecessary work. For instance,
if w eonly do partial unrolling, we don't break LCSSA, so we don't need
to rebuild it. Also, if all exits from the inner loop are inside the
enclosing loop, then complete unrolling won't break LCSSA either.
I replaced unconditional LCSSA recomputation with conditional recomputation +
unconditional assert and added several tests, which were failing when I
experimented with it.
Soon I plan to follow up with a similar patch for recalculation of dominators
tree.
Reviewers: hfinkel, dexonsmith, bogner, joker.eph, chandlerc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14526
llvm-svn: 253126
attribute.
Even if the target supports shrink-wrapping, the prologue and epilogue
must not move because a crash can happen anywhere and sanitizers need
to be able to unwind from the PC of the crash.
llvm-svn: 253116
This allows us to transform the below loop into a memcpy.
void test(unsigned *__restrict__ a, unsigned *__restrict__ b) {
for (int i = 2047; i >= 0; --i) {
a[i] = b[i];
}
}
This is the memcpy version of r251518, which added support for memset with
negative strided loops.
llvm-svn: 253091
The C++ EH personality automatically restores ESP from the C++ EH
registration node after a catchret. I mistakenly thought it was like
SEH, which does not restore ESP.
It makes sense for C++ EH to differ from SEH here because SEH does not
use funclets for catches, and does not allow catching inside of finally.
C++ EH may need to unwind through multiple catch funclets and eventually
catchret to some outer funclet. Therefore, the runtime has to keep track
of which ESP to use with catchret, rather than having the compiler
reload it manually.
llvm-svn: 253084
Use ScalarEvolution to calculate memory access bounds.
Handle function calls based on readnone/nocapture attributes.
Handle memory intrinsics with constant size.
This change improves both recall and precision of IsAllocaSafe.
See the new tests (ex. BitCastWide) for the kind of code that was wrongly
classified as safe.
SCEV efficiency seems to be limited by the fact the SafeStack runs late
(in CodeGenPrepare), and many loops are unrolled or otherwise not in LCSSA.
llvm-svn: 253083
This patch is enabling combining UNPCKL with vector_shuffle that moves the upper
half of a vector into the lower half, into a UNPCKH instruction. For example:
t2: v16i8 = vector_shuffle<8,9,10,11,12,13,14,15,u,u,u,u,u,u,u,u> t1, undef:v16i8
t3: v16i8 = X86ISD::UNPCKL undef:v16i8, t2
will be combined to:
t3: v16i8 = X86ISD::UNPCKH undef:v16i8, t1
Differential revision: http://reviews.llvm.org/D14399
llvm-svn: 253067
This is a recommit of 252842 which was reverted in 252859. The issue was
using %s format specifier for a StringRef - used Format's
left_justify(StringRef, int) instead.
It'd be nice to have __attribute__((format(..))) on llvm::format, but
apparently it's only implemented for c-style variadics, not C++ variadic
templates. Perhaps we could fix that & conditionalize the attribute on
such...
llvm-svn: 253065
Charlie Turner