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r227290 | dblaikie | 2015-01-27 18:34:53 -0800 (Tue, 27 Jan 2015) | 1 line
PR22356: DebugInfo: Handle the size of a member where the type of that member is a typedef (or other sugar) of a declaration.
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r227319 | bsteinbr | 2015-01-28 08:35:59 -0800 (Wed, 28 Jan 2015) | 10 lines
Fix LLVMSetMetadata and LLVMAddNamedMetadataOperand for single value MDNodes
Summary:
MetadataAsValue uses a canonical format that strips the MDNode if it
contains only a single constant value. This triggers an assertion when
trying to cast the value to a MDNode.
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D7165
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r227085 | joerg | 2015-01-26 03:41:48 -0800 (Mon, 26 Jan 2015) | 13 lines
The canonical CPU variant for ARM according to config.guess uses a
suffix it seems:
# ./config.guess
earmv7hfeb-unknown-netbsd7.99.4
Extend the triple parsing to support this. Avoid running the ARM parser
multiple times because StringSwitch is not lazy.
Reviewers: Renato Golin, Tim Northover
Differential Revision: http://reviews.llvm.org/D7166
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r226945 | thomas.stellard | 2015-01-23 17:05:45 -0500 (Fri, 23 Jan 2015) | 9 lines
R600/SI: Move i64 -> v2i32 load promotion into AMDGPUDAGToDAGISel::Select()
We used to do this promotion during DAG legalization, but this
caused an infinite loop in ExpandUnalignedLoad() because it assumed
that i64 loads were legal if i64 was a legal type.
It also seems better to report i64 loads as legal, since they actually
are and we were just promoting them to simplify our tablegen files.
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r227250 | ab | 2015-01-27 13:52:16 -0800 (Tue, 27 Jan 2015) | 31 lines
[SimplifyLibCalls] Don't confuse strcpy_chk for stpcpy_chk.
This was introduced in a faulty refactoring (r225640, mea culpa):
the tests weren't testing the return values, so, for both
__strcpy_chk and __stpcpy_chk, we would return the end of the
buffer (matching stpcpy) instead of the beginning (for strcpy).
The root cause was the prefix "__" being ignored when comparing,
which made us always pick LibFunc::stpcpy_chk.
Pass the LibFunc::Func directly to avoid this kind of error.
Also, make the testcases as explicit as possible to prevent this.
The now-useful testcases expose another, entangled, stpcpy problem,
with the further simplification. This was introduced in a
refactoring (r225640) to match the original behavior.
However, this leads to problems when successive simplifications
generate several similar instructions, none of which are removed
by the custom replaceAllUsesWith.
For instance, InstCombine (the main user) doesn't erase the
instruction in its custom RAUW. When trying to simplify say
__stpcpy_chk:
- first, an stpcpy is created (fortified simplifier),
- second, a memcpy is created (normal simplifier), but the
stpcpy call isn't removed.
- third, InstCombine later revisits the instructions,
and simplifies the first stpcpy to a memcpy. We now have
two memcpys.
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This fixes pr22351.
Original messages:
r226026:
Fix handling of extern_weak. This was broken by r225983
r226031:
Fix linking of shared libraries.
In shared libraries the plugin can see non-weak declarations that are still
undefined.
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r227300 | chandlerc | 2015-01-28 01:52:14 -0800 (Wed, 28 Jan 2015) | 34 lines
[LPM] Rip all of ManagedStatic and ThreadLocal out of the pretty stack
tracing code.
Managed static was just insane overhead for this. We took memory fences
and external function calls in every path that pushed a pretty stack
frame. This includes a multitude of layers setting up and tearing down
passes, the parser in Clang, everywhere. For the regression test suite
or low-overhead JITs, this was contributing to really significant
overhead.
Even the LLVM ThreadLocal is really overkill here because it uses
pthread_{set,get}_specific logic, and has careful code to both allocate
and delete the thread local data. We don't actually want any of that,
and this code in particular has problems coping with deallocation. What
we want is a single TLS pointer that is valid to use during global
construction and during global destruction, any time we want. That is
exactly what every host compiler and OS we use has implemented for
a long time, and what was standardized in C++11. Even though not all of
our host compilers support the thread_local keyword, we can directly use
the platform-specific keywords to get the minimal functionality needed.
Provided this limited trial survives the build bots, I will move this to
Compiler.h so it is more widely available as a light weight if limited
alternative to the ThreadLocal class. Many thanks to David Majnemer for
helping me think through the implications across platforms and craft the
MSVC-compatible syntax.
The end result is *substantially* faster. When running llc in a tight
loop over a small IR file targeting the aarch64 backend, this improves
its performance by over 10% for me. It also seems likely to fix the
remaining regressions seen by JIT users with threading enabled.
This may actually have more impact on real-world compile times due to
the use of the pretty stack tracing utility throughout the rest of Clang
or LLVM, but I've not collected any detailed measurements.
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r227299 | chandlerc | 2015-01-28 01:47:21 -0800 (Wed, 28 Jan 2015) | 48 lines
[LPM] A targeted but somewhat horrible fix to the legacy pass manager's
querying of the pass registry.
The pass manager relies on the static registry of PassInfo objects to
perform all manner of its functionality. I don't understand why it does
much of this. My very vague understanding is that this registry is
touched both during static initialization *and* while each pass is being
constructed. As a consequence it is hard to make accessing it not
require a acquiring some lock. This lock ends up in the hot path of
setting up, tearing down, and invaliditing analyses in the legacy pass
manager.
On most systems you can observe this as a non-trivial % of the time
spent in 'ninja check-llvm'. However, I haven't really seen it be more
than 1% in extreme cases of compiling more real-world software,
including LTO.
Unfortunately, some of the GPU JITs are seeing this taking essentially
all of their time because they have very small IR running through
a small pass pipeline very many times (at least, this is the vague
understanding I have of it).
This patch tries to minimize the cost of looking up PassInfo objects by
leveraging the fact that the objects themselves are immutable and they
are allocated separately on the heap and so don't have their address
change. It also requires a change I made the last time I tried to debug
this problem which removed the ability to de-register a pass from the
registry. This patch creates a single access path to these objects
inside the PMTopLevelManager which memoizes the result of querying the
registry. This is somewhat gross as I don't really know if
PMTopLevelManager is the *right* place to put it, and I dislike using
a mutable member to memoize things, but it seems to work.
For long-lived pass managers this should completely eliminate
the cost of acquiring locks to look into the pass registry once the
memoized cache is warm. For 'ninja check' I measured about 1.5%
reduction in CPU time and in total time on a machine with 32 hardware
threads. For normal compilation, I don't know how much this will help,
sadly. We will still pay the cost while we populate the memoized cache.
I don't think it will hurt though, and for LTO or compiles with many
small functions it should still be a win. However, for tight loops
around a pass manager with many passes and small modules, this will help
tremendously. On the AArch64 backend I saw nearly 50% reductions in time
to complete 2000 cycles of spinning up and tearing down the pipeline.
Measurements from Owen of an actual long-lived pass manager show more
along the lines of 10% improvements.
Differential Revision: http://reviews.llvm.org/D7213
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r227294 | chandlerc | 2015-01-27 20:57:56 -0800 (Tue, 27 Jan 2015) | 23 lines
[LPM] Stop using the string based preservation API. It is an
abomination.
For starters, this API is incredibly slow. In order to lookup the name
of a pass it must take a memory fence to acquire a pointer to the
managed static pass registry, and then potentially acquire locks while
it consults this registry for information about what passes exist by
that name. This stops the world of LLVMs in your process no matter
how little they cared about the result.
To make this more joyful, you'll note that we are preserving many passes
which *do not exist* any more, or are not even analyses which one might
wish to have be preserved. This means we do all the work only to say
"nope" with no error to the user.
String-based APIs are a *bad idea*. String-based APIs that cannot
produce any meaningful error are an even worse idea. =/
I have a patch that simply removes this API completely, but I'm hesitant
to commit it as I don't really want to perniciously break out-of-tree
users of the old pass manager. I'd rather they just have to migrate to
the new one at some point. If others disagree and would like me to kill
it with fire, just say the word. =]
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r227261 | compnerd | 2015-01-27 14:57:39 -0800 (Tue, 27 Jan 2015) | 6 lines
SymbolRewriter: allow rewriting with comdats
COMDATs must be identically named to the symbol. When support for COMDATs was
introduced, the symbol rewriter was not updated, resulting in rewriting failing
for symbols which were placed into COMDATs. This corrects the behaviour and
adds test cases for this.
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r227260 | compnerd | 2015-01-27 14:57:35 -0800 (Tue, 27 Jan 2015) | 4 lines
SymbolRewriter: prevent unnecessary rewrite
The rewrite for the pattern based rewrite is unnecessary if the existing name
matches the pattern.
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r227005 | dsanders | 2015-01-24 14:35:11 +0000 (Sat, 24 Jan 2015) | 38 lines
[mips] Fix 'jumpy' debug line info around calls.
Summary:
At the moment, address calculation is taking the debug line info from the
address node (e.g. TargetGlobalAddress). When a function is called multiple
times, this results in output of the form:
.loc $first_call_location
.. address calculation ..
.. function call ..
.. address calculation ..
.loc $second_call_location
.. function call ..
.loc $first_call_location
.. address calculation ..
.loc $third_call_location
.. function call ..
This patch makes address calculations for function calls take the debug line
info for the call node and results in output of the form:
.loc $first_call_location
.. address calculation ..
.. function call ..
.loc $second_call_location
.. address calculation ..
.. function call ..
.loc $third_call_location
.. address calculation ..
.. function call ..
All other address calculations continue to use the address node.
Test Plan: Fixes test/DebugInfo/multiline.ll on a mips host.
Subscribers: dblaikie, llvm-commits
Differential Revision: http://reviews.llvm.org/D7050
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r226664 | tnorthover | 2015-01-21 07:43:31 -0800 (Wed, 21 Jan 2015) | 7 lines
AArch64: add backend option to reserve x18 (platform register)
AAPCS64 says that it's up to the platform to specify whether x18 is
reserved, and a first step on that way is to add a flag controlling
it.
From: Andrew Turner <andrew@fubar.geek.nz>
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r226711 | jroelofs | 2015-01-21 14:39:43 -0800 (Wed, 21 Jan 2015) | 8 lines
Fix load-store optimizer on thumbv4t
Thumbv4t does not have lo->lo copies other than MOVS,
and that can't be predicated. So emit MOVS when needed
and bail if there's a predicate.
http://reviews.llvm.org/D6592
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r226708 | majnemer | 2015-01-21 14:32:04 -0800 (Wed, 21 Jan 2015) | 4 lines
InstCombine: Don't strip bitcasts off of callsites marked 'thunk'
The return type of a thunk is meaningless, we just want the arguments
and return value to be forwarded.
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r226755 | sanjoy | 2015-01-21 16:48:47 -0800 (Wed, 21 Jan 2015) | 11 lines
Make ScalarEvolution less aggressive with respect to no-wrap flags.
ScalarEvolution currently lowers a subtraction recurrence to an add
recurrence with the same no-wrap flags as the subtraction. This is
incorrect because `sub nsw X, Y` is not the same as `add nsw X, -Y`
and `sub nuw X, Y` is not the same as `add nuw X, -Y`. This patch
fixes the issue, and adds two test cases demonstrating the bug.
Differential Revision: http://reviews.llvm.org/D7081
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r226597 | thomas.stellard | 2015-01-20 14:33:04 -0500 (Tue, 20 Jan 2015) | 5 lines
R600/SI: Add subtarget feature to enable VGPR spilling for all shader types
This is disabled by default, but can be enabled with the subtarget
feature: 'vgpr-spilling'
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r226586 | thomas.stellard | 2015-01-20 12:49:47 -0500 (Tue, 20 Jan 2015) | 6 lines
R600/SI: Use external symbols for scratch buffer
We were passing the scratch buffer address to the shaders via user sgprs,
but now we use external symbols and have the driver patch the shader
using reloc information.
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r226585 | thomas.stellard | 2015-01-20 12:49:45 -0500 (Tue, 20 Jan 2015) | 5 lines
R600/SI: Add kill flag when copying scratch offset to a register
This allows us to re-use the same register for the scratch offset
when accessing large private arrays.
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r226584 | thomas.stellard | 2015-01-20 12:49:43 -0500 (Tue, 20 Jan 2015) | 6 lines
R600/SI: Don't store scratch buffer frame index in MUBUF offset field
We don't have a good way of legalizing this if the frame index offset
is more than the 12-bits, which is size of MUBUF's offset field, so
now we store the frame index in the vaddr field.
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r226583 | thomas.stellard | 2015-01-20 12:49:41 -0500 (Tue, 20 Jan 2015) | 5 lines
R600/SI: Update SIInstrInfo:verifyInstruction() after r225662
Now that we have our own custom register operand types, we need
to handle them in the verifiier.
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r226226 | Matthew.Arsenault | 2015-01-15 18:17:03 -0500 (Thu, 15 Jan 2015) | 5 lines
R600/SI: Fix trailing comma with modifiers
Instructions with 1 operand can still use source modifiers,
so make sure we don't print an extra comma afterwards.
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r226191 | marek.olsak | 2015-01-15 13:43:06 -0500 (Thu, 15 Jan 2015) | 11 lines
R600/SI: Unify VOP2 instructions which are VOP3-only on VI
This removes some duplicated classes and definitions.
These instructions are defined:
_e32 // pseudo
_e32_si
_e64 // pseudo
_e64_si
_e64_vi
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r226190 | marek.olsak | 2015-01-15 13:43:01 -0500 (Thu, 15 Jan 2015) | 2 lines
R600/SI: Use 64-bit encoding by default for opcodes that are VOP3-only on VI
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r226189 | marek.olsak | 2015-01-15 13:42:55 -0500 (Thu, 15 Jan 2015) | 6 lines
R600/SI: Add V_READLANE_B32 and V_WRITELANE_B32 for VI
These are VOP3-only on VI.
The new multiclass doesn't define VOP3 versions of VOP2 instructions.
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r226188 | marek.olsak | 2015-01-15 13:42:51 -0500 (Thu, 15 Jan 2015) | 7 lines
R600/SI: Don't shrink instructions whose e32 encoding doesn't exist
v2: modify hasVALU32BitEncoding instead
v3: - add pseudoToMCOpcode helper to AMDGPUInstInfo, which is used by both
hasVALU32BitEncoding and AMDGPUMCInstLower::lower
- report an error if a pseudo can't be lowered
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r226473 | garious | 2015-01-19 09:40:05 -0800 (Mon, 19 Jan 2015) | 8 lines
[AArch64] Implement GHC calling convention
Original patch by Luke Iannini. Minor improvements and test added by
Erik de Castro Lopo.
Differential Revision: http://reviews.llvm.org/D6877
From: Erik de Castro Lopo <erikd@mega-nerd.com>
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r226170 | vkalintiris | 2015-01-15 15:36:04 +0000 (Thu, 15 Jan 2015) | 7 lines
Fix the C-API MCJIT test for 32-bit big endian machines.
Avoid using unions for storing the return value from
LLVMGetGlobalValueAddress() and LLVMGetFunctionAddress() and accessing it as
a pointer through another pointer member. This causes problems on 32-bit big
endian machines since the pointer gets the higher part of the return value of
the aforementioned functions.
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r225644 is a revert of r225644. A fixed version for trunk is being reviewed, but there is
no need to rush this into 3.6.
Original message:
Revert "Add r224985 back with two fixes."
This reverts commit r225644 while I debug a regression.
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r226075 | sanjoy | 2015-01-14 17:46:09 -0800 (Wed, 14 Jan 2015) | 10 lines
Fix PR22222
The bug was introduced in r225282. r225282 assumed that sub X, Y is
the same as add X, -Y. This is not correct if we are going to upgrade
the sub to sub nuw. This change fixes the issue by making the
optimization ignore sub instructions.
Differential Revision: http://reviews.llvm.org/D6979
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r226048 | dexonsmith | 2015-01-14 14:27:36 -0800 (Wed, 14 Jan 2015) | 17 lines
IR: Move MDLocation into place
This commit moves `MDLocation`, finishing off PR21433. There's an
accompanying clang commit for frontend testcases. I'll attach the
testcase upgrade script I used to PR21433 to help out-of-tree
frontends/backends.
This changes the schema for `DebugLoc` and `DILocation` from:
!{i32 3, i32 7, !7, !8}
to:
!MDLocation(line: 3, column: 7, scope: !7, inlinedAt: !8)
Note that empty fields (line/column: 0 and inlinedAt: null) don't get
printed by the assembly writer.
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r226044 | dexonsmith | 2015-01-14 13:58:17 -0800 (Wed, 14 Jan 2015) | 15 lines
IR: Drop metadata references more aggressively during teardown
Sometimes teardown happens before the debug info graph is complete
(e.g., when clang throws an error). In that case, `MDNode`s will still
have RAUW, so deleting constants that the `MDNode`s point at will be
relatively expensive -- it'll cause re-uniquing all up the chain (what
I've been referring to as "teardown madness").
So, drop references *before* deleting constants. We need to drop a few
more references now: the metadata side of the metadata/value bridges
needs to be dropped off the cliff along with the rest of it (previously,
the bridges were cleaned before we did anything with the `MDNode`s).
There's no real functionality change here -- state before and after
`LLVMContextImpl::~LLVMContextImpl()` is unchanged -- so no testcase.
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r226029 | dexonsmith | 2015-01-14 11:56:10 -0800 (Wed, 14 Jan 2015) | 7 lines
IR: Fix a use-after-free in RAUW
Happened pretty commonly during `LLVMContext` teardown when `clang -g`
hit an error. This fixes the use-after-free. Next I'll clean up
teardown so that it's not RAUW'ing when metadata-tracked values are
deleted (only really causes a problem if the graph is mid-construction
when teardown starts, but it's still unnecessary work).
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r226023 | majnemer | 2015-01-14 11:26:56 -0800 (Wed, 14 Jan 2015) | 3 lines
InstCombine: Don't take A-B<0 into A<B if A-B has other uses
This fixes PR22226.
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Hans Wennborg
Tom Stellard
Rafael Espindola
Daniel Sanders
Pekka Jaaskelainen
Duncan P. N. Exon Smith