clang optimizes tail calls, as in this example:
int foo(void);
int bar(void) {
return foo();
}
where the call is transformed to:
calll .L0$pb
.L0$pb:
popl %eax
.Ltmp0:
addl $_GLOBAL_OFFSET_TABLE_+(.Ltmp0-.L0$pb), %eax
movl foo@GOT(%eax), %eax
popl %ebp
jmpl *%eax # TAILCALL
However, the GOT references must all be resolved at dlopen() time, and so this
approach cannot be used with lazy dynamic linking (e.g. using RTLD_LAZY), which
usually populates the PLT with stubs that perform the actual resolving.
This patch changes X86TargetLowering::LowerCall() to skip tail call
optimization, if the called function is a global or external symbol.
Patch by Dimitry Andric!
PR15086
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195318 91177308-0d34-0410-b5e6-96231b3b80d8
The instruction definitions incorrectly specified that popcntd and popcntw have
record forms; they do not. This mistake was causing invalid code generation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195272 91177308-0d34-0410-b5e6-96231b3b80d8
We now only allow breaking source order if the exit block frequency is
significantly higher than the other exit block. The actual bias is
currently under a flag so the best cut-off can be found; the flag
defaults to the old behavior. The idea is to get some benchmark coverage
over different values for the flag and pick the best one.
When we require the new frequency to be at least 20% higher than the old
frequency I see a 5% speedup on zlib's deflate when compressing a random
file on x86_64/westmere. Hal reported a small speedup on Fhourstones on
a BG/Q and no regressions in the test suite.
The test case is the full long_match function from zlib's deflate. I was
reluctant to add it for previous tweaks to branch probabilities because
it's large and potentially fragile, but changed my mind since it's an
important use case and more likely to break with all the current work
going into the PGO infrastructure.
Differential Revision: http://llvm-reviews.chandlerc.com/D2202
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195265 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Directives are being ignored, when they occur between a partial-word false
match and any match on another prefix.
For example, with FOO and BAR prefixes:
_FOO
FOO: foo
BAR: bar
FileCheck incorrectly matches:
fog
bar
This happens because FOO falsely matched as a partial word at '_FOO' and was
ignored while BAR matched at 'BAR:'. The match of BAR is incorrectly returned
as the 'first match' causing the FOO directive to be discarded.
Fixed this the same way as r194565 (D2166) did for a similar test case.
The partial-word false match should be counted as a match for the purposes of
finding the first match of a prefix, but should be returned as a false match
using CheckTy::CheckNone so that it isn't treated as a directive.
Fixes PR17995
Reviewers: samsonov, arsenm
Reviewed By: samsonov
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D2228
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195248 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of permanently outputting "MVLL" as the file checksum, clang
will create gcno and gcda checksums by hashing the destination block
numbers of every arc. This allows for llvm-cov to check if the two gcov
files are synchronized.
Regenerated the test files so they contain the checksum. Also added
negative test to ensure error when the checksums don't match.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195191 91177308-0d34-0410-b5e6-96231b3b80d8
Masking operations (where only some number of the low bits are being kept) are
selected to rldicl(x, 0, mb). If x is a logical right shift (which would become
rldicl(y, 64-n, n)), we might be able to fold the two instructions together:
rldicl(rldicl(x, 64-n, n), 0, mb) -> rldicl(x, 64-n, mb) for n <= mb
The right shift is really a left rotate followed by a mask, and if the explicit
mask is a more-restrictive sub-mask of the mask implied by the shift, only one
rldicl is needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195185 91177308-0d34-0410-b5e6-96231b3b80d8
Emit DW_TAG_type_units into the debug_info section using compile unit
headers. This is bogus/unusable by debuggers, but testable and provides
more isolated review.
Subsequent patches will include support for type unit headers and
emission into the debug_types section, as well as comdat grouping the
types based on their hash. Also the CompileUnit type will be renamed
'Unit' and relevant portions pulled out into respective CompileUnit and
TypeUnit types.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195166 91177308-0d34-0410-b5e6-96231b3b80d8
We are slicing an array of Value pointers and process those slices in a loop.
The problem is that we might invalidate a later slice by vectorizing a former
slice.
Use a WeakVH to track the pointer. If the pointer is deleted or RAUW'ed we can
tell.
The test case will only fail when running with libgmalloc.
radar://15498655
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195162 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of processing relocation for branch to stubs right away, emit a
modified relocation and add it to queue to be resolved later when final load
address is known.
This resolves seven MIPS MCJIT issues that were caused by missing relocation
fixups at the end.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195157 91177308-0d34-0410-b5e6-96231b3b80d8
The object files we support use null terminated strings, so there is no way to
support these.
This patch adds an assert to catch bad API use and an error check in the .ll
parser.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195155 91177308-0d34-0410-b5e6-96231b3b80d8
This is the first step to fix pr17918.
It extends the .section directive a bit, inspired by what the ELF one looks
like. The problem with using linkonce is that given
.section foo
.linkonce....
.section foo
.linkonce
we would already have switched sections when getting to .linkonce. The cleanest
solution seems to be to add the comdat information in the .section itself.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195148 91177308-0d34-0410-b5e6-96231b3b80d8
Hard float for mips16 means essentially to compile as soft float but to
use a runtime library for soft float that is written with native mips32
floating point instructions (those runtime routines run in mips32 hard
float mode).
The patch reviewed by Reed Kotler.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195123 91177308-0d34-0410-b5e6-96231b3b80d8
order of slices of the alloca which have exactly the same size and other
properties. This was found by a perniciously unstable sort
implementation used to flush out buggy uses of the algorithm.
The fundamental idea is that findCommonType should return the best
common type it can find across all of the slices in the range. There
were two bugs here previously:
1) We would accept an integer type smaller than a byte-width multiple,
and if there were different bit-width integer types, we would accept
the first one. This caused an actual failure in the testcase updated
here when the sort order changed.
2) If we found a bad combination of types or a non-load, non-store use
before an integer typed load or store we would bail, but if we found
the integere typed load or store, we would use it. The correct
behavior is to always use an integer typed operation which covers the
partition if one exists.
While a clever debugging sort algorithm found problem #1 in our existing
test cases, I have no useful test case ideas for #2. I spotted in by
inspection when looking at this code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195118 91177308-0d34-0410-b5e6-96231b3b80d8
A column limit in the test folder can lead to trouble as the RUN, CHECK,
etc. comments can potentially be broken over multiple lines changing
their meaning. Without column limit, clang-format will simply keep the
test author's line breaks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195100 91177308-0d34-0410-b5e6-96231b3b80d8
No true functional changes.
Change the "hack" name of emitMipsHackSTOCG to emitSymSTO.
Remove demonstration code in AsmParser for emitMipsHackSTOCG and
emitMipsHackELFFlags. The STO field is in an ELF symbol and is not
an explicit directive. That said, we are missing the compliment call
in AsmParser and that will need to be addressed soon.
XFAIL dummy tests for emitMipsHackELFFlags and emitMipsHackELFFlags.
These will built out with following patches.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195067 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r190888, to fix PR17967. The original change wasn't
the right way to get @feat.00 into the object file. The right fix is to
make @feat.00 be a global symbol.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195053 91177308-0d34-0410-b5e6-96231b3b80d8
lowering only for load/stores to scalar allocas. The resulting values
confuse the backend and don't add anything because we can describe
array-allocas with a dbg.declare intrinsic just fine.
rdar://problem/15464571
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195052 91177308-0d34-0410-b5e6-96231b3b80d8
(except functions marked always_inline).
Functions with 'optnone' must also have 'noinline' so they don't get
inlined into any other function.
Based on work by Andrea Di Biagio.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195046 91177308-0d34-0410-b5e6-96231b3b80d8
Test doesn't actually check the output. I need
to fix add i64 being matched for the addressing
calculations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195040 91177308-0d34-0410-b5e6-96231b3b80d8
In some case the loop exit count computation can overflow. Extend the type to
prevent most of those cases.
The problem is loops like:
int main ()
{
int a = 1;
char b = 0;
lbl:
a &= 4;
b--;
if (b) goto lbl;
return a;
}
The backedge count is 255. The induction variable type is i8. If we add one to
255 to get the exit count we overflow to zero.
To work around this issue we extend the type of the induction variable to i32 in
the case of i8 and i16.
PR17532
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195008 91177308-0d34-0410-b5e6-96231b3b80d8
Fixed an inappropriate use of BuildPairF64 when compiling for MIPS32 with FP64
which resulted in an impossible constraint on the register allocation. It now
uses BuildPairF64_64.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195007 91177308-0d34-0410-b5e6-96231b3b80d8
