1) PR25154. This is basically a repeat of PR18102, which was fixed in
r200201, and broken again by r234430. The latter changed which of the
store nodes was merged into from the first to the last. Thus, we now
also need to prefer merging a later store at a given address into the
target node, instead of an earlier one.
2) While investigating that, I also realized I'd introduced a bug in
r236850. There, I removed a check for alignment -- not realizing that
nothing except the alignment check was ensuring that none of the stores
were overlapping! This is a really bogus way to ensure there's no
aliased stores.
A better solution to both of these issues is likely to always use the
code added in the 'if (UseAA)' branches which rearrange the chain based
on a more principled analysis. I'll look into whether that can be used
always, but in the interest of getting things back to working, I think a
minimal change makes sense.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251816 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
SCEV Predicates represent conditions that typically cannot be derived from
static analysis, but can be used to reduce SCEV expressions to forms which are
usable for different optimizers.
ScalarEvolution now has the rewriteUsingPredicate method which can simplify a
SCEV expression using a SCEVPredicateSet. The normal workflow of a pass using
SCEVPredicates would be to hold a SCEVPredicateSet and every time assumptions
need to be made a new SCEV Predicate would be created and added to the set.
Each time after calling getSCEV, the user will call the rewriteUsingPredicate
method.
We add two types of predicates
SCEVPredicateSet - implements a set of predicates
SCEVEqualPredicate - tests for equality between two SCEV expressions
We use the SCEVEqualPredicate to re-implement stride versioning. Every time we
version a stride, we will add a SCEVEqualPredicate to the context.
Instead of adding specific stride checks, LoopVectorize now adds a more
generic SCEV check.
We only need to add support for this in the LoopVectorizer since this is the
only pass that will do stride versioning.
Reviewers: mzolotukhin, anemet, hfinkel, sanjoy
Subscribers: sanjoy, hfinkel, rengolin, jmolloy, llvm-commits
Differential Revision: http://reviews.llvm.org/D13595
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251800 91177308-0d34-0410-b5e6-96231b3b80d8
This revision has introduced an issue that only affects bootstrapped compiler
when it is printing the ASM. It turns out that the new code path taken due to
legalizing a scalar_to_vector of i64 -> v2i64 exposes a missing check in a
micro optimization to change a load followed by a scalar_to_vector into a
load and splat instruction on PPC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251798 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The new function sys::path::user_cache_directory tries to discover
a directory suitable for cache storage for current system user.
On Windows and Darwin it returns a path to system-specific user cache directory.
On Linux it follows XDG Base Directory Specification, what is:
- use non-empty $XDG_CACHE_HOME env var,
- use $HOME/.cache.
Reviewers: chapuni, aaron.ballman, rafael
Subscribers: rafael, aaron.ballman, llvm-commits
Differential Revision: http://reviews.llvm.org/D13801
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251784 91177308-0d34-0410-b5e6-96231b3b80d8
1. Added a set of public interfaces in InstrProfRecord
class to access (read/write) value profile data.
2. Changed IndexedProfile reader and writer code to
use the newly defined interfaces and hide implementation
details.
3. Added a couple of unittests for value profiling:
- Test new interfaces to get and set value profile data
- Test value profile data merging with various scenarios.
No functional change is expected. The new interfaces will also
make it possible to change on-disk format of value prof data
to be more compact (to be submitted).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251771 91177308-0d34-0410-b5e6-96231b3b80d8
Have `getConstantEvolutionLoopExitValue` work correctly with multiple
entry loops.
As far as I can tell, `getConstantEvolutionLoopExitValue` never did the
right thing for multiple entry loops; and before r249712 it would
silently return an incorrect answer. r249712 changed SCEV to fail an
assert on a multiple entry loop, and this change fixes the underlying
issue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251770 91177308-0d34-0410-b5e6-96231b3b80d8
Optimized <8 x i32> to <8 x i16>
<4 x i64> to < 4 x i32>
<16 x i16> to <16 x i8>
All these oprtrations use now AVX512F set (KNL). Before this change it was implemented with AVX2 set.
Differential Revision: http://reviews.llvm.org/D14108
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251764 91177308-0d34-0410-b5e6-96231b3b80d8
This adds support for COFF I386. This is sufficient for code execution in a
32-bit JIT, though, imported symbols need to custom lowered for the redirection.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251761 91177308-0d34-0410-b5e6-96231b3b80d8
We never need to pass end(). This will also remove some complication
once we start adding error checking.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251758 91177308-0d34-0410-b5e6-96231b3b80d8
Prevent `createNodeFromSelectLikePHI` from creating SCEV expressions
that break LCSSA.
A better fix for the same issue is to teach SCEVExpander to not break
LCSSA by inserting PHI nodes at appropriate places. That's planned for
the future.
Fixes PR25360.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251756 91177308-0d34-0410-b5e6-96231b3b80d8
The initial coverage checking code for sample records failed to count
records inside inlined profiles. This change fixes the oversight.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251752 91177308-0d34-0410-b5e6-96231b3b80d8
This is a bit ugly, but has a few advantages:
* Archive is now easy to copy since there is no Archive -> Child -> Archive
loop.
* It makes it clear that we already checked for errors when finding the Child
data.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251750 91177308-0d34-0410-b5e6-96231b3b80d8
underlying memory, and will automatically release it on destruction.
Use this to tidy up the orc::IndirectStubsInfo class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251731 91177308-0d34-0410-b5e6-96231b3b80d8
This is a really straightforward port. Also adds a test for the pass,
since it only seemed to be tested tangentially before.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251726 91177308-0d34-0410-b5e6-96231b3b80d8
from its pass harness by providing a lambda to query for AA results.
This allows the legacy pass to easily provide a lambda that uses the
special helpers to construct function AA results from a legacy CGSCC
pass. With the new pass manager (the next patch) the lambda just
directly wraps the intuitive query API.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251715 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
When forming expressions for phi nodes having an incoming value from
outside the loop A and a value coming from the previous iteration B
we were forming an AddRec if:
- B was an AddRec
- the value A was equal to the value for B at iteration -1 (or equal
to the value of B shifted by one iteration, at iteration 0)
In this case, we were computing the expression to be the expression of
B, shifted by one iteration.
This changes generalizes the logic above by removing the restriction that
B needs to be an AddRec. For this we introduce two expression rewriters
that allow us to
- shift an expression by one iteration
- get the value of an expression at iteration 0
This allows us to get SCEV expressions for PHI nodes when these expressions
are not AddRecExprs.
Reviewers: sanjoy
Subscribers: llvm-commits, sanjoy
Differential Revision: http://reviews.llvm.org/D14175
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251700 91177308-0d34-0410-b5e6-96231b3b80d8
Update the discriminator assignment algorithm
* If a scope has already been assigned a discriminator, do not reassign a nested discriminator for it.
* If the file and line both match, even if the column does not match, we should assign a new discriminator for the stmt.
original code:
; #1 int foo(int i) {
; #2 if (i == 3 || i == 5) return 100; else return 99;
; #3 }
; i == 3: discriminator 0
; i == 5: discriminator 2
; return 100: discriminator 1
; return 99: discriminator 3
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251689 91177308-0d34-0410-b5e6-96231b3b80d8
Update the discriminator assignment algorithm
* If a scope has already been assigned a discriminator, do not reassign a nested discriminator for it.
* If the file and line both match, even if the column does not match, we should assign a new discriminator for the stmt.
original code:
; #1 int foo(int i) {
; #2 if (i == 3 || i == 5) return 100; else return 99;
; #3 }
; i == 3: discriminator 0
; i == 5: discriminator 2
; return 100: discriminator 1
; return 99: discriminator 3
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251685 91177308-0d34-0410-b5e6-96231b3b80d8
* If a scope has already been assigned a discriminator, do not reassign a nested discriminator for it.
* If the file and line both match, even if the column does not match, we should assign a new discriminator for the stmt.
original code:
; #1 int foo(int i) {
; #2 if (i == 3 || i == 5) return 100; else return 99;
; #3 }
; i == 3: discriminator 0
; i == 5: discriminator 2
; return 100: discriminator 1
; return 99: discriminator 3
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251680 91177308-0d34-0410-b5e6-96231b3b80d8
Introduce LLVMSymbolizer::symbolizeInlinedCode() instead of switching
on PrintInlining option passed to the constructor. This will be needed
once we retrun structured data (instead of std::string) from
LLVMSymbolizer and move printing logic out.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251675 91177308-0d34-0410-b5e6-96231b3b80d8
This assert was reachable from user input. A minimized test case (no
FUNCTION_BLOCK_ID record) is attached.
Bug found with afl-fuzz
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251667 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This is mostly NFC. It is a first step in cleaning up LLVMSymbolize
library. It removes "ModuleInfo" class which bundles together ObjectFile
and its debug info context in favor of:
* abstract SymbolizableModule in public headers;
* SymbolizableObjectFile subclass in implementation.
Additionally, SymbolizableObjectFile is now created via factory, so we
can properly detect object parsing error at this stage instead of keeping
the broken half-parsed object. As a next step, we would be able to
propagate the error all the way back to the library user.
Further improvements might include:
* factoring out the logic of finding appropriate file with debug info
for a given object file, and caching all parsed object files into a
separate class [A].
* factoring out DILineInfo rendering [B].
This would make what is now a heavyweight "LLVMSymbolizer" a relatively
straightforward class, that calls into [A] to turn filepath into a
SymbolizableModule, delegates actual symbolization to concrete SymbolizableModule
implementation, and lets [C] render the result.
Reviewers: dblaikie, echristo, rafael
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14099
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251662 91177308-0d34-0410-b5e6-96231b3b80d8
This patch generalizes the zeroing of vector elements with the BLEND instructions. Currently a zero vector will only blend if the shuffled elements are correctly inline, this patch recognises when a vector input is zero (or zeroable) and modifies a local copy of the shuffle mask to support a blend. As a zeroable vector input may not be all zeroes, the zeroable vector is regenerated if necessary.
Differential Revision: http://reviews.llvm.org/D14050
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251659 91177308-0d34-0410-b5e6-96231b3b80d8
than a pre-allocated slab of stubs. Also add a convenience method for creating a
single stub, rather than a whole block a time.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251658 91177308-0d34-0410-b5e6-96231b3b80d8
transformations in FunctionAttrs rather than building a new one each
time.
This isn't trivial because there are different heuristics from different
passes for exactly what set they want. The primary difference is whether
an *overridable* function completely disables the synthesis of
attributes. I've modeled this by directly testing for overridable, and
using the common set that excludes external and opt-none functions.
This does cause some changes by disabling more optimizations in the face
of opt-none. Specifically, we were still optimizing *calls* to opt-none
functions based on their attributes, just not the bodies. It seems
better to be conservative on both fronts given the intended semanticas
here (best effort to not assume or disturb anything). I've not tried to
test this change as it seems complex, brittle, and not important to the
implicit contract of opt-none. Instead, it seems more like a choice that
should be dictated by the simplified implementation and the change to be
acceptable differences within the space of opt-none.
A big benefit here is that these transformations no longer rely on the
legacy pass manager's SCC types, they just work on generic sets of
function pointers. This will make it easy to re-use their logic in the
new pass manager.
I've also made the transforms static functions instead of members where
trivial while I was touching the signatures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251640 91177308-0d34-0410-b5e6-96231b3b80d8
This was discovered to be necessary while running memchr-01.ll with
-verify-machinstrs, because it is not allowed to have a phys reg live
accross block boundaries while on SSA form, if the register is
allocatable (expect in entry block and landing pads).
In this test case, stringRRE pseudos are expanded after isel by adding
a loop block which produces a live out CC register. To make the test
pass, it was also necessary to not say that StringRRELoop pseudo uses
R0L, this is only true for the StringRRE opcode.
-verify-machineinstrs added to memchr-01.ll test.
New test case int-cmp-51.ll to test that MachineCSE can eliminate
an identical compare (which it couldn't do before).
Reviewed by Ulrich Weigand
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251634 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This commit resolves wrong opcodes for ll and sc instructions for r6 architecutres, which were generated in method MipsTargetLowering::emitAtomicBinary.
Author: Jelena.Losic
Reviewers: dsanders
Subscribers: dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D13593
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251629 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
ARMv6KZ cores were set up incorrectly in ARM.td; also, the SMI mnemonic
(the old name for SMC, as defined in ARMv6KZ) wasn't supported.
Reviewers: jmolloy, rengolin
Subscribers: aemerson, rengolin, llvm-commits
Differential Revision: http://reviews.llvm.org/D14154
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251627 91177308-0d34-0410-b5e6-96231b3b80d8
This patch unify the 39-bit and 42-bit mapping for aarch64 to use only
one instrumentation algorithm. This removes compiler flag
SANITIZER_AARCH64_VMA requirement for MSAN on aarch64.
The mapping to use now is for 39 and 42-bits:
0x00000000000ULL-0x01000000000ULL MappingDesc::INVALID
0x01000000000ULL-0x02000000000ULL MappingDesc::SHADOW
0x02000000000ULL-0x03000000000ULL MappingDesc::ORIGIN
0x03000000000ULL-0x04000000000ULL MappingDesc::SHADOW
0x04000000000ULL-0x05000000000ULL MappingDesc::ORIGIN
0x05000000000ULL-0x06000000000ULL MappingDesc::APP
0x06000000000ULL-0x07000000000ULL MappingDesc::INVALID
0x07000000000ULL-0x08000000000ULL MappingDesc::APP
And only for 42-bits:
0x08000000000ULL-0x09000000000ULL MappingDesc::INVALID
0x09000000000ULL-0x0A000000000ULL MappingDesc::SHADOW
0x0A000000000ULL-0x0B000000000ULL MappingDesc::ORIGIN
0x0B000000000ULL-0x0F000000000ULL MappingDesc::INVALID
0x0F000000000ULL-0x10000000000ULL MappingDesc::APP
0x10000000000ULL-0x11000000000ULL MappingDesc::INVALID
0x11000000000ULL-0x12000000000ULL MappingDesc::APP
0x12000000000ULL-0x17000000000ULL MappingDesc::INVALID
0x17000000000ULL-0x18000000000ULL MappingDesc::SHADOW
0x18000000000ULL-0x19000000000ULL MappingDesc::ORIGIN
0x19000000000ULL-0x20000000000ULL MappingDesc::INVALID
0x20000000000ULL-0x21000000000ULL MappingDesc::APP
0x21000000000ULL-0x26000000000ULL MappingDesc::INVALID
0x26000000000ULL-0x27000000000ULL MappingDesc::SHADOW
0x27000000000ULL-0x28000000000ULL MappingDesc::ORIGIN
0x28000000000ULL-0x29000000000ULL MappingDesc::SHADOW
0x29000000000ULL-0x2A000000000ULL MappingDesc::ORIGIN
0x2A000000000ULL-0x2B000000000ULL MappingDesc::APP
0x2B000000000ULL-0x2C000000000ULL MappingDesc::INVALID
0x2C000000000ULL-0x2D000000000ULL MappingDesc::SHADOW
0x2D000000000ULL-0x2E000000000ULL MappingDesc::ORIGIN
0x2E000000000ULL-0x2F000000000ULL MappingDesc::APP
0x2F000000000ULL-0x39000000000ULL MappingDesc::INVALID
0x39000000000ULL-0x3A000000000ULL MappingDesc::SHADOW
0x3A000000000ULL-0x3B000000000ULL MappingDesc::ORIGIN
0x3B000000000ULL-0x3C000000000ULL MappingDesc::APP
0x3C000000000ULL-0x3D000000000ULL MappingDesc::INVALID
0x3D000000000ULL-0x3E000000000ULL MappingDesc::SHADOW
0x3E000000000ULL-0x3F000000000ULL MappingDesc::ORIGIN
0x3F000000000ULL-0x40000000000ULL MappingDesc::APP
And although complex it provides a better memory utilization that
previous one.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251624 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The microMIPS register class GPRMM16 does not contain the $zero register.
However, MipsSEDAGToDAGISel::replaceUsesWithZeroReg() would replace uses
of the $dst register:
[d]addiu, $dst, $zero, 0
with the $zero register, without checking for membership in the register
class of the target machine operand.
Reviewers: dsanders
Subscribers: llvm-commits, dsanders
Differential Revision: http://reviews.llvm.org/D13984
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251622 91177308-0d34-0410-b5e6-96231b3b80d8
Since the verifier will give false reports if it incorrectly thinks MI is
loading or storing using an FI, it is necessary to scan memoperands and
find out how the FI is used in the instruction. This should be relatively
rare.
Needed to make CodeGen/SystemZ/spill-01.ll pass, which now runs with this flag.
Reviewed by Quentin Colombet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251620 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Conversion opcode name format should be f64.convert_u/i64 not f64_convert_u
Author: s3ththompson
Reviewers: jfb
Subscribers: sunfish, jfb, llvm-commits, dschuff
Differential Revision: http://reviews.llvm.org/D14160
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251613 91177308-0d34-0410-b5e6-96231b3b80d8
This was a layering violation in ScheduleDAGInstrs (and
MachineSchedulerBase) they both shouldn't know directly whether they are
used by the PostMachineScheduler or the MachineScheduler.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251608 91177308-0d34-0410-b5e6-96231b3b80d8
Somewhat shockingly for an analysis pass which is computing constant ranges, LVI did not understand the ranges provided by range metadata.
As part of this change, I included a change to CVP primarily because doing so made it much easier to write small self contained test cases. CVP was previously only handling the non-local operand case, but given that LVI can sometimes figure out information about instructions standalone, I don't see any reason to restrict this. There could possibly be a compile time impact from this, but I suspect it should be minimal. If anyone has an example which substaintially regresses, please let me know. I could restrict the block local handling to ICmps feeding Terminator instructions if needed.
Note that this patch continues a somewhat bad practice in LVI. In many cases, we know facts about values, and separate context sensitive facts about values. LVI makes no effort to distinguish and will frequently cache the same value fact repeatedly for different contexts. I would like to change this, but that's a large enough change that I want it to go in separately with clear documentation of what's changing. Other examples of this include the non-null handling, and arguments.
As a meta comment: the entire motivation of this change was being able to write smaller (aka reasonable sized) test cases for a future patch teaching LVI about select instructions.
Differential Revision: http://reviews.llvm.org/D13543
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251606 91177308-0d34-0410-b5e6-96231b3b80d8
Follow on to http://reviews.llvm.org/D13074, implementing something pointed out by Sanjoy. His truth table from his comment on that bug summarizes things well:
LHS | RHS | LHS >=s RHS | LHS implies RHS
0 | 0 | 1 (0 >= 0) | 1
0 | 1 | 1 (0 >= -1) | 1
1 | 0 | 0 (-1 >= 0) | 0
1 | 1 | 1 (-1 >= -1) | 1
The key point is that an "i1 1" is the value "-1", not "1".
Differential Revision: http://reviews.llvm.org/D13756
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251597 91177308-0d34-0410-b5e6-96231b3b80d8
The most common use case is when eliminating redundant range checks in an example like the following:
c = a[i+1] + a[i];
Note that all the smarts of the transform (the implication engine) is already in ValueTracking and is tested directly through InstructionSimplify.
Differential Revision: http://reviews.llvm.org/D13040
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251596 91177308-0d34-0410-b5e6-96231b3b80d8
To be able to maximize the bandwidth during vectorization, this patch provides a new flag vectorizer-maximize-bandwidth. When it is turned on, the vectorizer will determine the vectorization factor (VF) using the smallest instead of widest type in the loop. To avoid increasing register pressure too much, estimates of the register usage for different VFs are calculated so that we only choose a VF when its register usage doesn't exceed the number of available registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251592 91177308-0d34-0410-b5e6-96231b3b80d8
We cannot form ctr-based loops around function calls, including calls to
__tls_get_addr used for PIC TLS variables. References to such TLS variables,
however, might be buried within constant expressions, and so we need to search
the entire constant expression to be sure that no references to such TLS
variables exist.
Fixes PR25256, reported by Eric Schweitz. This is a slightly-modified version
of the patch suggested by Eric in the bug report, and a test case I created.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251582 91177308-0d34-0410-b5e6-96231b3b80d8
As a follow-up to r251566, do the same for the other optionally-supported
register classes (mostly for vector registers). Don't return an unavailable
register class (which would cause an assert later), but fail cleanly when
provided an unsupported inline asm constraint.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251575 91177308-0d34-0410-b5e6-96231b3b80d8
The most substantial changes are again for watchOS: libcalls are hard-float if
needed and sincos has a different calling convention.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251571 91177308-0d34-0410-b5e6-96231b3b80d8
At the LLVM level this ABI is essentially a minimal modification of AAPCS to
support 16-byte alignment for vector types and the stack.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251570 91177308-0d34-0410-b5e6-96231b3b80d8
These MachO file directives are used by linkers and other tools to provide
compatibility information, much like the existing .ios_version_min and
.macosx_version_min.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251569 91177308-0d34-0410-b5e6-96231b3b80d8
This adds the flag -mllvm -sample-profile-check-coverage=N to the
SampleProfile pass. N is the percent of input sample records that the
user expects to apply. If the pass does not use N% (or more) of the
sample records in the input, it emits a warning.
This is useful to detect some forms of stale profiles. If the code has
drifted enough from the original profile, there will be records that do
not match the IR anymore.
This will not detect cases where a sample profile record for line L is
referring to some other instructions that also used to be at line L.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251568 91177308-0d34-0410-b5e6-96231b3b80d8
When crbits are disabled, cleanly reject the constraint (return the register
class only to cause an assert later).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251566 91177308-0d34-0410-b5e6-96231b3b80d8
