It looks like the code this patch deletes is based on a misunderstanding of
what guarantees writev provides. In particular, writev with 1 iovec is
not "more atomic" than a write.
Testing on OS X shows that both write and writev from multiple processes
can be intermixed.
llvm-svn: 255837
This matches the other MIB methods, none of which modify the builder.
Without this, we can't chain copyImplicitOps.
Also reformat the few users, in PPCEarlyReturn.
llvm-svn: 255828
Summary: Surface counter overflow when merging profile data. Merging still occurs on overflow but counts saturate to the maximum representable value. Overflow is reported to the user.
Reviewers: davidxl, dnovillo, silvas
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15547
llvm-svn: 255825
The access function has a short entry and a short exit, the initialization
block is only run the first time. To improve the performance, we want to
have a short frame at the entry and exit.
We explicitly handle most of the CSRs via copies. Only the CSRs that are not
handled via copies will be in CSR_SaveList.
Frame lowering and prologue/epilogue insertion will generate a short frame
in the entry and exit according to CSR_SaveList. The majority of the CSRs will
be handled by register allcoator. Register allocator will try to spill and
reload them in the initialization block.
We add CSRsViaCopy, it will be explicitly handled during lowering.
1> we first set FunctionLoweringInfo->SplitCSR if conditions are met (the target
supports it for the given machine function and the function has only return
exits). We also call TLI->initializeSplitCSR to perform initialization.
2> we call TLI->insertCopiesSplitCSR to insert copies from CSRsViaCopy to
virtual registers at beginning of the entry block and copies from virtual
registers to CSRsViaCopy at beginning of the exit blocks.
3> we also need to make sure the explicit copies will not be eliminated.
The target independent portion was committed as r255353.
rdar://problem/23557469
Differential Revision: http://reviews.llvm.org/D15341
llvm-svn: 255821
Update supportSplitCSR's interface to take machine function instead of the
calling convention.
Review comments for http://reviews.llvm.org/D15341
llvm-svn: 255818
As of r255720, the loop pass manager will DTRT when passes update the
loop info for removed loops, so they no longer need to reach into
LPPassManager APIs to do this kind of transformation. This change very
nearly removes the need for the LPPassManager to even be passed into
loop passes - the only remaining pass that uses the LPM argument is
LoopUnswitch.
llvm-svn: 255797
increase
Summary:
This patch adds a function called getRegPressureSetScore() to
TargetRegisterInfo. The MachineScheduler uses this when comparing
instruction that increase the register pressure of different sets
to determine which set is safer to increase.
This hook is useful for GPU targets where the number of registers in the
class is not the best metric for determing which presser set is safer to
increase.
Future work may include adding more parameters to this function, like
for example, the current pressure level of the set or the amount that
the pressure will be increased/decreased.
Reviewers: qcolombet, escha, arsenm, atrick, MatzeB
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14806
llvm-svn: 255795
When considering incoming values as part of a reduction phi, ensure the
incoming value is dominated by said phi.
Failing to ensure this property causes miscompiles.
Fixes PR25787.
Many thanks to Mattias Eriksson for reporting, reducing and analyzing the
problem for me.
Differential Revision: http://reviews.llvm.org/D15580
llvm-svn: 255792
This generates a compile_commands.json file, which tells tools like
YouCompleteMe and clang_complete exactly how to build each source file.
Patch by Justin Lebar!
llvm-svn: 255789
The SystemZ linkers provide an optimization to transform a general-
or local-dynamic TLS sequence into an initial-exec sequence if possible.
Do do that, the compiler generates a function call to __tls_get_offset,
which is a brasl instruction annotated with *two* relocations:
- a R_390_PLT32DBL to install __tls_get_offset as branch target
- a R_390_TLS_GDCALL / R_390_TLS_LDCALL to inform the linker that
the TLS optimization should be performed if possible
If the optimization is performed, the brasl is replaced by an ld load
instruction.
However, *both* relocs are processed independently by the linker.
Therefore it is crucial that the R_390_PLT32DBL is processed *first*
(installing the branch target for the brasl) and the R_390_TLS_GDCALL
is processed *second* (replacing the whole brasl with an ld).
If the relocs are swapped, the linker will first replace the brasl
with an ld, and *then* install the __tls_get_offset branch target
offset. Since ld has a different layout than brasl, this may even
result in a completely different (or invalid) instruction; in any
case, the resulting code is corrupted.
Unfortunately, the way the MC common code sorts relocations causes
these two to *always* end up the wrong way around, resulting in
wrong code generation by the linker and crashes.
This patch overrides the sortRelocs routine to detect this particular
pair of relocs and enforce the required order.
llvm-svn: 255787
When comparing a zero-extended value against a constant small enough to
be in range of the inner type, it doesn't matter whether a signed or
unsigned compare operation (for the outer type) is being used. This is
why the code in adjustSubwordCmp had this assertion:
assert(C.ICmpType == SystemZICMP::Any &&
"Signedness shouldn't matter here.");
assuming the the caller had already detected that fact. However, it
turns out that there cases, in particular with always-true or always-
false conditions that have not been eliminated when compiling at -O0,
where this is not true.
Instead of failing an assertion if C.ICmpType is not SystemZICMP::Any
here, we can simply *set* it safely to SystemZICMP::Any, however.
llvm-svn: 255786
This removes an unpleasant hack involving a global variable for special
lowering of certain memcpy calls. These are now lowered as intended in
EmitTargetCodeForMemcpy in the same way that other targets do it.
llvm-svn: 255785
One of the earlier patches updated the cmake rule to install the
runtime dlls in INSTALL_DIR/lib which is not correct. This patch
updates the rule to install CMake's RUNTIME in bin directory
Differential Revision: http://reviews.llvm.org/D15505
llvm-svn: 255781
Add a function VLIWPacketizerList::shouldAddToPacket, which will allow
specific implementations to decide if it is profitable to add given
instruction to the current packet.
llvm-svn: 255780
Summary:
This patch introduces two new function attributes
InaccessibleMemOnly: This attribute indicates that the function may only access memory that is not accessible by the program/IR being compiled. This is a weaker form of ReadNone.
inaccessibleMemOrArgMemOnly: This attribute indicates that the function may only access memory that is either not accessible by the program/IR being compiled, or is pointed to by its pointer arguments. This is a weaker form of ArgMemOnly
Test cases have been updated. This revision uses this (d001932f3a) as reference.
Reviewers: jmolloy, hfinkel
Subscribers: reames, joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D15499
llvm-svn: 255778
In conditional store merging, we were creating PHIs when we didn't
need to. If the value to be predicated isn't defined in the block
we're predicating, then it doesn't need a PHI at all (because we only
deal with triangles and diamonds, any value not in the predicated BB
must dominate the predicated BB).
This fixes a large code size increase in some benchmarks in a popular embedded benchmark suite.
Now with a fix (and fixed tests) for the conformance issue seen in Chromium.
llvm-svn: 255767
ARMv8.2-A adds 16-bit floating point versions of all existing SIMD
floating-point instructions. This is an optional extension, so all of
these instructions require the FeatureFullFP16 subtarget feature.
Note that VFP without SIMD is not a valid combination for any version of
ARMv8-A, but I have ensured that these instructions all depend on both
FeatureNEON and FeatureFullFP16 for consistency.
Differential Revision: http://reviews.llvm.org/D15039
llvm-svn: 255764
ARMv8.2-A adds 16-bit floating point versions of all existing VFP
floating-point instructions. This is an optional extension, so all of
these instructions require the FeatureFullFP16 subtarget feature.
The assembly for these instructions uses S registers (AArch32 does not
have H registers), but the instructions have ".f16" type specifiers
rather than ".f32" or ".f64". The top 16 bits of each source register
are ignored, and the top 16 bits of the destination register are set to
zero.
These instructions are mostly the same as the 32- and 64-bit versions,
but they use coprocessor 9 rather than 10 and 11.
Two new instructions, VMOVX and VINS, have been added to allow packing
and extracting two 16-bit floats stored in the top and bottom halves of
an S register.
New fixup kinds have been added for the PC-relative load and store
instructions, but no ELF relocations have been added as they have a
range of 512 bytes.
Differential Revision: http://reviews.llvm.org/D15038
llvm-svn: 255762
This folds (ashr (shl a, [56,48,32,24,16]), SarConst)
into (shl, (sext (a), [56,48,32,24,16] - SarConst))
or into (lshr, (sext (a), SarConst - [56,48,32,24,16]))
depending on sign of (SarConst - [56,48,32,24,16])
sexts in X86 are MOVs.
The MOVs have the same code size as above SHIFTs (only SHIFT by 1 has lower code size).
However the MOVs have 2 advantages to SHIFTs on x86:
1. MOVs can write to a register that differs from source.
2. MOVs accept memory operands.
This fixes PR24373.
Patch by: evgeny.v.stupachenko@intel.com
Differential Revision: http://reviews.llvm.org/D13161
llvm-svn: 255761
Summary: On Windows, the allocation granularity can be significantly
larger than a page (64K), so with many small objects, just clearing
the FreeMem list rapidly leaks quite a bit of virtual memory space
(if not rss). Fix that by only removing those parts of the FreeMem
blocks that overlap pages for which we are applying memory permissions,
rather than dropping the FreeMem blocks entirely.
Reviewers: lhames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15202
llvm-svn: 255760
Summary: This patch adds a check in visitLandingPad to see if landingpad's result type is token type. If so, do not create DAG nodes for its exception pointer and selector value. This patch enables the back end to handle landingpads of token type.
Reviewers: JosephTremoulet, majnemer, rnk
Subscribers: sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D15405
llvm-svn: 255749
