Summary:
We need to add a runtime memcheck for pair of accesses (x,y) where at least one of x and y
are writes.
Assuming we have w writes and r reads, currently this number is estimated as being
w* (w+r-1). This estimation will count (write,write) pairs twice and will overestimate
the number of checks required.
This change adds a getNumberOfChecks method to RuntimePointerCheck, which
will count the number of runtime checks needed (similar in implementation to
needsAnyChecking) and uses it to produce the correct number of runtime checks.
Test Plan:
llvm test suite
spec2k
spec2k6
Performance results: no changes observed (not surprising since the formula for 1 writer is basically the same, which would covers most cases - at least with the current check limit).
Reviewers: anemet
Reviewed By: anemet
Subscribers: mzolotukhin, llvm-commits
Differential Revision: http://reviews.llvm.org/D10217
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239295 91177308-0d34-0410-b5e6-96231b3b80d8
Interleaved memory accesses are grouped and vectorized into vector load/store and shufflevector.
E.g. for (i = 0; i < N; i+=2) {
a = A[i]; // load of even element
b = A[i+1]; // load of odd element
... // operations on a, b, c, d
A[i] = c; // store of even element
A[i+1] = d; // store of odd element
}
The loads of even and odd elements are identified as an interleave load group, which will be transfered into vectorized IRs like:
%wide.vec = load <8 x i32>, <8 x i32>* %ptr
%vec.even = shufflevector <8 x i32> %wide.vec, <8 x i32> undef, <4 x i32> <i32 0, i32 2, i32 4, i32 6>
%vec.odd = shufflevector <8 x i32> %wide.vec, <8 x i32> undef, <4 x i32> <i32 1, i32 3, i32 5, i32 7>
The stores of even and odd elements are identified as an interleave store group, which will be transfered into vectorized IRs like:
%interleaved.vec = shufflevector <4 x i32> %vec.even, %vec.odd, <8 x i32> <i32 0, i32 4, i32 1, i32 5, i32 2, i32 6, i32 3, i32 7>
store <8 x i32> %interleaved.vec, <8 x i32>* %ptr
This optimization is currently disabled by defaut. To try it by adding '-enable-interleaved-mem-accesses=true'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239291 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
canUnrollCompletely takes `unsigned` values for `UnrolledCost` and
`RolledDynamicCost` but is passed in `uint64_t`s that are silently
truncated. Because of this, when `UnrolledSize` is a large integer
that has a small remainder with UINT32_MAX, LLVM tries to completely
unroll loops with high trip counts.
Reviewers: mzolotukhin, chandlerc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10293
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239218 91177308-0d34-0410-b5e6-96231b3b80d8
CVP wants to analyze the condition operand of a select along an edge.
It succeeds in getting back a Constant but not a ConstantInt. Instead,
it gets a ConstantExpr. It then assumes that the Constant must be equal
to false because it isn't equal to true.
Instead, perform an additional comparison.
This fixes PR23752.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239217 91177308-0d34-0410-b5e6-96231b3b80d8
If we have (select a, b, c), it is sometimes valid to simplify this to a
single select operand. However, doing so is only valid if the
computation doesn't inject poison into the computation.
It might be helpful to consider the following example:
(select (icmp ne %i, INT_MAX), (add nsw %i, 1), INT_MIN)
The select is equivalent to (add %i, 1) but not (add nsw %i, 1).
Self hosting on x86_64 revealed that this occurs very, very rarely so
bailing out is hopefully pretty reasonable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239215 91177308-0d34-0410-b5e6-96231b3b80d8
Linking the debug frame section is actually very easy as we just have to
patch the start address in the FDE header and then copy the rest of the
FDE without even looking at it. The only small complexity comes from the
handling of the CIEs that we should unique across object file. This is
also really easy by using a StringMap keyed on the raw contents of the
CIE.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239198 91177308-0d34-0410-b5e6-96231b3b80d8
The main use of the YAML debug map format is for testing inside LLVM. If we have IR
files in the tests used to generate object files, then we obviously don't know the
addresses of the symbols inside the object files beforehand.
This change lets the YAML import lookup the addresses in the object files and rewrite
them. This will allow to have test that really don't need any binary input.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239189 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r239141. This commit was an attempt to reintroduce
a previous patch that broke many self-hosting bots with clang timeouts,
but it still has slowdown issues, at least on ARM, increasing the
compilation time (stage 2, clang's) by 5x.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239175 91177308-0d34-0410-b5e6-96231b3b80d8
For targets with a free fneg, this fold is always a net loss if it
ends up duplicating the multiply, so definitely avoid it.
This might be true for some targets without a free fneg too, but
I'll leave that for future investigation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239167 91177308-0d34-0410-b5e6-96231b3b80d8
The new naming is (to me) much easier to understand. Here is a summary
of the new state of the world:
- '*Threshold' is the threshold for full unrolling. It is measured
against the estimated unrolled cost as computed by getUserCost in TTI
(or CodeMetrics, etc). We will exceed this threshold when unrolling
loops where unrolling exposes a significant degree of simplification
of the logic within the loop.
- '*PercentDynamicCostSavedThreshold' is the percentage of the loop's
estimated dynamic execution cost which needs to be saved by unrolling
to apply a discount to the estimated unrolled cost.
- '*DynamicCostSavingsDiscount' is the discount applied to the estimated
unrolling cost when the dynamic savings are expected to be high.
When actually analyzing the loop, we now produce both an estimated
unrolled cost, and an estimated rolled cost. The rolled cost is notably
a dynamic estimate based on our analysis of the expected execution of
each iteration.
While we're still working to build up the infrastructure for making
these estimates, to me it is much more clear *how* to make them better
when they have reasonably descriptive names. For example, we may want to
apply estimated (from heuristics or profiles) dynamic execution weights
to the *dynamic* cost estimates. If we start doing that, we would also
need to track the static unrolled cost and the dynamic unrolled cost, as
only the latter could reasonably be weighted by profile information.
This patch is sadly not without functionality change for the new unroll
analysis logic. Buried in the heuristic management were several things
that surprised me. For example, we never subtracted the optimized
instruction count off when comparing against the unroll heursistics!
I don't know if this just got lost somewhere along the way or what, but
with the new accounting of things, this is much easier to keep track of
and we use the post-simplification cost estimate to compare to the
thresholds, and use the dynamic cost reduction ratio to select whether
we can exceed the baseline threshold.
The old values of these flags also don't necessarily make sense. My
impression is that none of these thresholds or discounts have been tuned
yet, and so they're just arbitrary placehold numbers. As such, I've not
bothered to adjust for the fact that this is now a discount and not
a tow-tier threshold model. We need to tune all these values once the
logic is ready to be enabled.
Differential Revision: http://reviews.llvm.org/D9966
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239164 91177308-0d34-0410-b5e6-96231b3b80d8
These are added mainly for the benefit of clang, but this also means that they
are now allowed in .fpu directives and we emit the correct .fpu directive when
single-precision-only is used.
Differential Revision: http://reviews.llvm.org/D10238
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239151 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Only restoring AvailableFeatures is not enough and will lead to buggy behaviour.
For example, if we have a feature enabled and we ".set pop", the next time we try
to ".set" that feature nothing will happen because the "!(STI.getFeatureBits()[Feature])"
check will be false, because we didn't restore STI.FeatureBits.
In order to fix this, we need to make MipsAssemblerOptions remember the STI.FeatureBits
instead of the AvailableFeatures and then regenerate AvailableFeatures each time we ".set pop".
This is because, AFAIK, there is no way to convert from AvailableFeatures back to STI.FeatureBits,
but the reverse is possible by using ComputeAvailableFeatures(STI.FeatureBits).
I also moved the updating of AssemblerOptions inside the "if" statement in
setFeatureBits() and clearFeatureBits(), as there is no reason to update if
nothing changes.
Reviewers: dsanders, mkuper
Reviewed By: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9156
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239144 91177308-0d34-0410-b5e6-96231b3b80d8
isInductionPHI wants to calculate the stride based on the pointee size.
However, this is not possible when the pointee is zero sized.
This fixes PR23763.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239143 91177308-0d34-0410-b5e6-96231b3b80d8
Also, moved test cases from CodeGen/X86/fold-buildvector-bug.ll into
CodeGen/X86/buildvec-insertvec.ll and regenerated CHECK lines using
update_llc_test_checks.py.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239142 91177308-0d34-0410-b5e6-96231b3b80d8
I don't have the IR which is causing the build bot breakage but I can
postulate as to why they are timing out:
1. SimplifyWithOpReplaced was stripping flags from the simplified value.
2. visitSelectInstWithICmp was overriding SimplifyWithOpReplaced because
it's simplification wasn't correct.
3. InstCombine would revisit the add instruction and note that it can
rederive the flags.
4. By modifying the value, we chose to revisit instructions which reuse
the value. One of the instructions is the original select, causing
LLVM to never reach fixpoint.
Instead, strip the flags only when we are sure we are going to perform
the simplification.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239141 91177308-0d34-0410-b5e6-96231b3b80d8
This is breaking a lot of build bots and is causing very long-running
compiles (infinite loops)?
Likely, we shouldn't return nullptr?
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239139 91177308-0d34-0410-b5e6-96231b3b80d8
We cleverly handle cases where computation done in one argument of a select
instruction is suitable for the other operand, thus obviating the need
of the select and the comparison. However, the other operand cannot
have flags.
This fixes PR23757.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239115 91177308-0d34-0410-b5e6-96231b3b80d8
gc.statepoint intrinsics with a far immediate call target
were lowered incorrectly as pc-rel32 calls.
This change fixes the problem, and generates an indirect call
via a scratch register.
For example:
Intrinsic:
%safepoint_token = call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* inttoptr (i64 140727162896504 to void ()*), i32 0, i32 0, i32 0, i32 0)
Old Incorrect Lowering:
callq 140727162896504
New Correct Lowering:
movabsq $140727162896504, %rax
callq *%rax
In lowerCallFromStatepoint(), the callee-target was modified and
represented as a "TargetConstant" node, rather than a "Constant" node.
Undoing this modification enabled LowerCall() to generate the
correct CALL instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239114 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
A small bit that I missed when I updated the X86 backend to account for
the Win64 calling convention on non-Windows. Now we don't use dead
non-volatile registers when emitting a Win64 indirect tail call on
non-Windows.
Should fix PR23710.
Test Plan: Added test for the correct behavior based on the case I posted to PR23710.
Reviewers: rnk
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10258
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239111 91177308-0d34-0410-b5e6-96231b3b80d8
Report proper error code from MachOObjectFile constructor if we
can't parse another segment load command (we already return a proper
error if segment load command contents is suspicious).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239109 91177308-0d34-0410-b5e6-96231b3b80d8
The big/small ordering here is based on signed values so SmallValue will
be INT_MIN and BigValue 0. This shouldn't be a problem but the code
assumed that BigValue always had more bits set than SmallValue.
We used to just miss the transformation, but a recent refactoring of
mine turned this into an assertion failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239105 91177308-0d34-0410-b5e6-96231b3b80d8
NVPTXISelDAGToDAG translates "addrspacecast to param" to
NVPTX::nvvm_ptr_gen_to_param
Added an llc test in bug21465.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239100 91177308-0d34-0410-b5e6-96231b3b80d8
