Revert "Linker: Drop function pointers for overridden subprograms"
This reverts commit r233164 and its testcase follow-ups in r233165,
r233207, r233214, and r233221. It apparently unleashed an LTO bootstrap
failure, at least on Darwin:
Quentin Colombet [Thu, 26 Mar 2015 01:01:48 +0000 (01:01 +0000)]
[RegisterCoalescer] Add a rule to consider more profitable copies first when
those are in the same basic block.
The previous approach was the topological order of the basic block.
Eric Christopher [Thu, 26 Mar 2015 00:50:23 +0000 (00:50 +0000)]
Add computeFSAdditions to the function based subtarget creation
for PPC due to some unfortunate default setting via TargetMachine
creation. I've added a FIXME on how this can be unraveled in the
backend and a test to make sure we successfully legalize 64-bit things
if we say we're 64-bits.
Otherwise, broken input modules can cause assertions. I've updated two
of the testcases that started failing (modules that had `Require` flags
but didn't meet their own requirements), but Rafael and I decided that
test/Linker/2011-08-22-ResolveAlias.ll should just be deleted outright
-- it's a leftover of the way llvm-gcc used to implement weakref.
Simon Pilgrim [Wed, 25 Mar 2015 22:30:31 +0000 (22:30 +0000)]
[DAGCombiner] Add support for TRUNCATE + FP_EXTEND vector constant folding
This patch adds supports for the vector constant folding of TRUNCATE and FP_EXTEND instructions and tidies up the SINT_TO_FP and UINT_TO_FP instructions to match.
It also moves the vector constant folding for the FNEG and FABS instructions to use the DAG.getNode() functionality like the other unary instructions.
Linker: Stop using -gmlt test/Linker/subprogram-linkonce-weak.ll
As dblaikie pointed out, if I stop setting `emissionKind: 2` then the
backend won't do magical things on Linux vs. Darwin. I had wrongly
assumed that there were stricter requirements on the input if we weren't
in line-tables-only mode, but apparently not.
With that knowledge, clean up this testcase a little more.
- Set `emissionKind: 1`.
- Add back checks for the weak version of @foo.
- Check more robustly that we have the right subprograms by checking
the `DW_AT_decl_file` and `DW_AT_decl_line` which now show up.
- Check the line table in isolation (since it's no longer doubling as
an indirect test for the subprogram of the weak version of @foo).
Matthias Braun [Wed, 25 Mar 2015 21:18:24 +0000 (21:18 +0000)]
RegisterCoalescer: Fix implicit def handling in register coalescer
If liveranges induced by an IMPLICIT_DEF get completely covered by a
proper liverange the IMPLICIT_DEF instructions and its corresponding
definitions have to be removed from the live ranges. This has to happen
in the subregister live ranges as well (I didn't see this case earlier
because in most programs only some subregisters are covered and the
IMPLCIT_DEF won't get removed).
No testcase, I spent hours trying to create one for one of the public
targets, but ultimately failed because I couldn't manage to properly
control the placement of COPY and IMPLICIT_DEF instructions from an .ll
file.
Reid Kleckner [Wed, 25 Mar 2015 20:10:36 +0000 (20:10 +0000)]
WinEH: Create an unwind help alloca for __CxxFrameHandler3 xdata tables
We don't have any logic to emit those tables yet, so the sdag lowering
of this intrinsic is just a stub. We can see the intrinsic in the
prepared IR, though.
Rewrite the checks from r233164 that I temporarily disabled in r233165.
It turns out that the line-tables only debug info we emit from `llc` is
(intentionally) different on Linux than on Darwin. r218129 started
skipping emission of subprograms with no inlined subroutines, and
r218702 was a spiritual revert of that behaviour for Darwin.
I think we can still test this in a platform-neutral way.
- Stop checking for the possibly missing `DW_TAG_subprogram` defining
the debug info for the real version of `@foo`.
- Start checking the line tables, ensuring that the right debug info
was used to generate them (grabbing `DW_AT_low_pc` from the compile
unit).
- I changed up the line numbers used in the "weak" version so it's
easier to follow.
Kit Barton [Wed, 25 Mar 2015 19:36:23 +0000 (19:36 +0000)]
Add Hardware Transactional Memory (HTM) Support
This patch adds Hardware Transaction Memory (HTM) support supported by ISA 2.07
(POWER8). The intrinsic support is based on GCC one [1], but currently only the
'PowerPC HTM Low Level Built-in Function' are implemented.
The HTM instructions follows the RC ones and the transaction initiation result
is set on RC0 (with exception of tcheck). Currently approach is to create a
register copy from CR0 to GPR and comapring. Although this is suboptimal, since
the branch could be taken directly by comparing the CR0 value, it generates code
correctly on both test and branch and just return value. A possible future
optimization could be elimitate the MFCR instruction to branch directly.
The HTM usage requires a recently newer kernel with PPC HTM enabled. Tested on
powerpc64 and powerpc64le.
This is send along a clang patch to enabled the builtins and option switch.
DebugInfo: Permit DW_TAG_structure_type, DW_TAG_member, DW_TAG_typedef tags with empty file names.
Some languages, such as Go, have pre-defined structure types (e.g. "string"
is essentially a pointer/length pair) or pre-defined "typedef" types
(e.g. "error" is essentially a typedef for a specific interface type).
Such types do not have associated source location, so a Go frontend would
be correct not to associate a file name with such types.
This change relaxes the DIType verifier to permit unlocated types with
these tags.
Sanjay Patel [Wed, 25 Mar 2015 17:34:11 +0000 (17:34 +0000)]
use update_llc_test_checks.py to tighten checking in these tests
1. There were no CHECK-LABELs, so we could match instructions from the wrong function.
2. The use of zero operands meant multiple xor instructions could match some CHECKs.
3. The test was over-specified to need a Sandybridge CPU and Darwin triple.
Justin Bogner [Wed, 25 Mar 2015 08:07:47 +0000 (08:07 +0000)]
test: Fix the dependencies for the check-llvm-* targets
In r233009 we gained specific check-llvm-* build targets for invoking
specific parts of the test suite, but they were copying the
dependencies for check-all, rather than just listing the dependencies
for check-llvm.
This moves the creation of these targets next to the check-llvm
target, and uses that target's configuration rather than the check-all
config.
Craig Topper [Wed, 25 Mar 2015 04:16:50 +0000 (04:16 +0000)]
[X86] Remove GetCpuIDAndInfo, GetCpuIDAndInfoEx and DetectFamilyModel functions from X86 MC layer. They haven't been used since CPU autodetection was removed from X86Subtarget.cpp.
Linker: Temporarily disable dwarfdump checks from r233164
At least one Linux bot [1] doesn't like my dwarfdump checks, so I've
disable those until I can investigate what's going on there. I'll
continue to track this in PR22792.
Linker: Drop function pointers for overridden subprograms
Instead of dropping subprograms that have been overridden, just set
their function pointers to `nullptr`. This is a minor adjustment to the
stop-gap fix for PR21910 committed in r224487, and fixes the crasher
from PR22792.
The problem that r224487 put a band-aid on: how do we find the canonical
subprogram for a `Function`? Since the backend currently relies on
`DebugInfoFinder` (which does a naive in-order traversal of compile
units and picks the first subprogram) for this, r224487 tried dropping
non-canonical subprograms.
Dropping subprograms fails because the backend *also* builds up a map
from subprogram to compile unit (`DwarfDebug::SPMap`) based on the
subprogram lists. A missing subprogram causes segfaults later when an
inlined reference (such as in this testcase) is created.
Instead, just drop the `Function` pointer to `nullptr`, which nicely
mirrors what happens when an already-inlined `Function` is optimized
out. We can't really be sure that it's the same definition anyway, as
the testcase demonstrates.
This still isn't completely satisfactory. Two flaws at least that I can
think of:
- I still haven't found a straightforward way to make this symmetric
in the IR. (Interestingly, the DWARF output is already symmetric,
and I've tested for that to be sure we don't regress.)
- Using `DebugInfoFinder` to find the canonical subprogram for a
function is kind of crazy. We should just attach metadata to the
function, like this:
Paul Robinson [Wed, 25 Mar 2015 00:10:24 +0000 (00:10 +0000)]
'optnone' should not disable DAG combiner.
Reverts the code change from r221168 and the relevant test.
It was a mistake to disable the combiner, and based on the ultimate
definition of 'optnone' we shouldn't have considered the test case
as failing in the first place.
Philip Reames [Tue, 24 Mar 2015 23:54:54 +0000 (23:54 +0000)]
!invariant.load semantics with potentially clobbering calls
A load from an invariant location is assumed to not alias any otherwise potentially aliasing stores. Our implementation only applied this rule to store instructions themselves whereas they it should apply for any memory accessing instruction. This results in both FRE and PRE becoming more effective at eliminating invariant loads.
Note that as a follow on change I will likely move this into AliasAnalysis itself. That's where the TBAA constant flag is handled and the semantics are essentially the same. I'd like to separate the semantic change from the refactoring and thus have extended the hack that's already in MemoryDependenceAnalysis for this change.
Reid Kleckner [Tue, 24 Mar 2015 23:46:01 +0000 (23:46 +0000)]
X86: Fix frameescape when not using an FP
We can't use TargetFrameLowering::getFrameIndexOffset directly, because
Win64 really wants the offset from the stack pointer at the end of the
prologue. Instead, use X86FrameLowering::getFrameIndexOffsetFromSP(),
which is a pretty close approximiation of that. It fails to handle cases
with interestingly large stack alignments, which is pretty uncommon on
Win64 and is TODO.
Justin Bogner [Tue, 24 Mar 2015 23:34:36 +0000 (23:34 +0000)]
llvm-cov: Require a subcommand when invoked as llvm-cov
A while ago llvm-cov gained support for clang's instrumentation based
profiling in addition to its gcov support, and subcommands were added
to choose which behaviour to use. When no subcommand was specified, we
fell back to gcov compatibility with a warning that a subcommand would
be required in the future. Now, we require the subcommand.
Note that if the basename of llvm-cov is gcov (via symlink or
hardlink, for example), we still use the gcov compatible behaviour
with no subcommand required.
David Blaikie [Tue, 24 Mar 2015 23:34:31 +0000 (23:34 +0000)]
Opaque Pointer Types: GEP API migrations to specify the gep type explicitly
The changes to InstCombine (& SCEV) do seem a bit silly - it doesn't make
anything obviously better to have the caller access the pointers element
type (the thing I'm trying to remove) than the GEP itself, but it's a
helpful migration step. This will allow me to more obviously lock down
GEP (& Load, etc) API usage, then fix all the code that accesses pointer
element types except the places that need to be removed (most of the
InstCombines) anyway - at which point I'll need to just remove all that
code because it won't be meaningful anymore (there will be no pointer
types, so no bitcasts to combine)
SCEV looks like it'll need some restructuring - we'll have to do a bit
more work for GEP canonicalization, since it'll depend on how it's used
if we can even manage to canonicalize it to a non-ugly GEP. I guess we
can do some fun stuff like voting (do 2 out of 3 load from the GEP with
a certain type that gives a pretty GEP? Does every typed use of the GEP
use either a specific type or a generic type (i8*, etc)?)
Frederic Riss [Tue, 24 Mar 2015 23:11:07 +0000 (23:11 +0000)]
[dsymutil] Temporarily disable some tests on windows.
It seems one windows bot fails since I added ilne table linking to
llvm-dsymutil (see r232333 commit thread).
Disable the affected tests until I can figure out what's happening.
Sanjay Patel [Tue, 24 Mar 2015 22:39:29 +0000 (22:39 +0000)]
optimize the AVX2 (integer) version of vperm2 into a shuffle
...because this is what happens when an instruction
set puts its underwear on after its pants.
This is an extension of r232852, r233100, and 233110:
http://llvm.org/viewvc/llvm-project?view=revision&revision=232852
http://llvm.org/viewvc/llvm-project?view=revision&revision=233100
http://llvm.org/viewvc/llvm-project?view=revision&revision=233110
David Blaikie [Tue, 24 Mar 2015 22:38:16 +0000 (22:38 +0000)]
Opaque Pointer Types: GEP API migrations to specify the gep type explicitly
The changes to InstCombine do seem a bit silly - it doesn't make
anything obviously better to have the caller access the pointers element
type (the thing I'm trying to remove) than the GEP itself, but it's a
helpful migration step. This will allow me to more obviously lock down
GEP (& Load, etc) API usage, then fix all the code that accesses pointer
element types except the places that need to be removed (most of the
InstCombines) anyway - at which point I'll need to just remove all that
code because it won't be meaningful anymore (there will be no pointer
types, so no bitcasts to combine)
Philip Reames [Tue, 24 Mar 2015 22:28:45 +0000 (22:28 +0000)]
Merge empty landing pads in SimplifyCFG
This patch tries to merge duplicate landing pads when they branch to a common shared target.
Given IR that looks like this:
lpad1:
%exn = landingpad {i8*, i32} personality i32 (...)* @__gxx_personality_v0
cleanup
br label %shared_resume
lpad2:
%exn2 = landingpad {i8*, i32} personality i32 (...)* @__gxx_personality_v0
cleanup
br label %shared_resume
shared_resume:
call void @fn()
ret void
}
We can rewrite the users of both landing pad blocks to use one of them. This will generally allow the shared_resume block to be merged with the common landing pad as well.
Without this change, tail duplication would likely kick in - creating N (2 in this case) copies of the shared_resume basic block.
AArch64: use a different means to determine whether to byte swap relocations.
This code depended on a bug in the FindAssociatedSection function that would
cause it to return the wrong result for certain absolute expressions. Instead,
use EvaluateAsRelocatable.
David Blaikie [Tue, 24 Mar 2015 21:31:31 +0000 (21:31 +0000)]
Remove an InstCombine that seems to have become redundant.
Assert that this doesn't fire - I'll remove all of this later, but just
leaving it in for a while in case this is firing & we just don't have
test coverage.
Sanjay Patel [Tue, 24 Mar 2015 20:36:42 +0000 (20:36 +0000)]
[X86, AVX] instcombine vperm2 intrinsics with zero inputs into shuffles
This is the IR optimizer follow-on patch for D8563: the x86 backend patch
that converts this kind of shuffle back into a vperm2.
This is also a continuation of the transform that started in D8486.
In that patch, Andrea suggested that we could convert vperm2 intrinsics that
use zero masks into a single shuffle.
Sanjoy Das [Tue, 24 Mar 2015 19:29:22 +0000 (19:29 +0000)]
[IRCE] Fix how IRCE checks for no-sign-overflow.
IRCE requires the induction variables it handles to not sign-overflow.
The current scheme of checking if sext({X,+,S}) == {sext(X),+,sext(S)}
fails when SCEV simplifies sext(X) too. After this change we //also//
check no-signed-wrap by looking at the flags set on the SCEVAddRecExpr.
DebugInfo: Reorder definitions of MDLocation and MDFile, NFC
Move definition of `MDLocation` after `MDLocalScope` so that the latter
is available for casts in the former. Similarly, move the definition of
`MDFile` as early as possible so that other classes can cast to it in
their definitions. (Follow-up commits will take advantage of this.)
DebugInfo: Add MDLocalScope, a legal scope for locals
Add a subclass of `MDScope` to explicitly categorize the legal scopes
for locals -- in particular, scopes that are legal for `MDLocation`,
`MDLexicalBlockBase`, and `MDLocalVariable`. This provides a convenient
`isa<>` target for the verifier, and eventually I'll be changing the
above classes' `getScope()` to specifically return it. Currently, its
subclasses are `MDSubprogram`, `MDLexicalBlock`, and
`MDLexicalBlockFile`.
I've gone with `MDLocalScope` for now -- a little ambiguous since it's a
scope *for* locals, not a scope that's local -- but I'm open to more
descriptive names if someone can think of something better. Regardless,
the code docs should make it clear enough.
It still causes buildbot failures (gcc running out of memory on several platforms, and a self-host failure on arm), although less than the previous time.
Daniel Sanders [Tue, 24 Mar 2015 11:26:34 +0000 (11:26 +0000)]
[mips] Distinguish 'R', 'ZC', and 'm' inline assembly memory constraint.
Summary:
Previous behaviour of 'R' and 'm' has been preserved for now. They will be
improved in subsequent commits.
The offset permitted by ZC varies according to the subtarget since it is
intended to match the restrictions of the pref, ll, and sc instructions.
The restrictions on these instructions are:
* For microMIPS: 12-bit signed offset.
* For Mips32r6/Mips64r6: 9-bit signed offset.
* Otherwise: 16-bit signed offset.
James Molloy [Tue, 24 Mar 2015 11:15:23 +0000 (11:15 +0000)]
"float2int": Add a new pass to demote from float to int where possible.
It is possible to have code that converts from integer to float, performs operations then converts back, and the result is provably the same as if integers were used.
This can come from different sources, but the most obvious is a helper function that uses floats but the arguments given at an inlined callsites are integers.
This pass considers all integers requiring a bitwidth less than or equal to the bitwidth of the mantissa of a floating point type (23 for floats, 52 for doubles) as exactly representable in floating point.
To reduce the risk of harming efficient code, the pass only attempts to perform complete removal of inttofp/fptoint operations, not just move them around.
Previously, subtarget features were a bitfield with the underlying type being uint64_t.
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.
The first time this was committed (r229831), it caused several buildbot failures.
At least some of the ARM ones were due to gcc/binutils issues, and should now be fixed.
Lang Hames [Tue, 24 Mar 2015 04:07:01 +0000 (04:07 +0000)]
[Orc] Use std::string to capture name by value.
This just updates the code to reflect the comment, but this bug actually hit the
out-of-tree lazy demo. I'm working on a patch to add the lazy-demo's
functionality to lli so that we can test this in-tree soon.
DebugInfo: Overload get() in DIDescriptor subclasses
Continue to simplify the `DIDescriptor` subclasses, so that they behave
more like raw pointers. Remove `getRaw()`, replace it with an
overloaded `get()`, and overload the arrow and cast operators. Two
testcases started to crash on the arrow operators with this change
because of `scope:` references that weren't real scopes. I fixed them.
Soon I'll add verifier checks for them too.
This also adds explicit dereference operators. Previously, the builtin
dereference against `operator MDNode *()` would have worked, but now the
builtins are ambiguous.