The code in orderDepdences that looks at the order dependences between
instructions was processing all the successor and predecessor order
dependences. However, we really only want to check for an order dependence
for instructions scheduled in the same cycle.
Also, fixed how the pipeliner handles output dependences. An output
dependence is also a potential loop carried dependence. The pipeliner
didn't handle this case properly so an invalid schedule could be created
that allowed an output dependence to be scheduled in the next iteration
at the same cycle.
Patch by Brendon Cahoon.
llvm-svn: 328516
When the definition of a phi is used by a phi in the next iteration,
the pipeliner was assuming that the definition is processed first.
Because of the assumption, an incorrect phi name was used. This patch
has a check to see if the phi definition has been processed already.
Patch by Brendon Cahoon.
llvm-svn: 328510
The software pipeliner attempts to delete dead instructions after
generating the pipelined loop. The code looks for uses of each
instruction. Physical registers should be treated differently because
the use chains do not exist. The code that checks for dead
instructions should assume that definitions of physical registers
are used if the operand doesn't contain the dead flag.
Patch by Brendon Cahoon.
llvm-svn: 328509
The pipeliner needs to be conservative when updating the memoperands
of instructions in the epilog. Previously, the pipeliner was changing
the offset of the memoperand based upon the scheduling stage. However,
that is incorrect when control flow branches around the kernel code.
The bug enabled a load and store to the same stack offset to be swapped.
This patch fixes the bug by updating the size of the memoperands to be
UINT_MAX. This conservative value means that dependences will be created
between other loads and stores.
Patch by Brendon Cahoon.
llvm-svn: 328508
Summary:
We previously emulated multi-staged builds using two dockerfiles,
native support from Docker allows us to merge them into one,
simplifying our scripts.
For more details about multi-stage builds, see:
https://docs.docker.com/develop/develop-images/multistage-build/
Reviewers: mehdi_amini, klimek, sammccall
Reviewed By: sammccall
Subscribers: llvm-commits, ioeric, cfe-commits
Differential Revision: https://reviews.llvm.org/D44787
llvm-svn: 328503
This replaces a large chunk of code that was looking for compound
patterns that include these sub-patterns. Existing tests ensure that
all of the previous examples are still folded as expected.
We still need to loosen the FMF check.
llvm-svn: 328502
Document that flag -resource-pressure can be used to enable/disable the resource
pressure view. This change should have been part of r328305.
llvm-svn: 328492
Implement TTI interface for targets to indicate that the LSR should give
priority to post-incrementing addressing modes.
Combination of patches by Sebastian Pop and Brendon Cahoon.
Differential Revision: https://reviews.llvm.org/D44758
llvm-svn: 328490
The goal of this patch is to address most of PR36874. To fully fix PR36874 we
need to split the "InstructionInfo" view from the "SummaryView". That would make
easy to check the latency and rthroughput as well.
The patch reuses all the logic from ResourcePressureView to print out the
"instruction tables".
We have an entry for every instruction in the input sequence. Each entry reports
the theoretical resource pressure distribution. Resource pressure is uniformly
distributed across all the processor resource units of a group.
At the moment, the backend pipeline is not configurable, so the only way to fix
this is by creating a different driver that simply sends instruction events to
the resource pressure view. That means, we don't use the Backend interface.
Instead, it is simpler to just have a different code-path for when flag
-instruction-tables is specified.
Once Clement addresses bug 36663, then we can port the "instruction tables"
logic into a stage of our configurable pipeline.
Updated the BtVer2 test cases (thanks Simon for the help). Now we pass flag
-instruction-tables to each modified test.
Differential Revision: https://reviews.llvm.org/D44839
llvm-svn: 328487
Current logic of loop SCEV invalidation in Loop Unroller implicitly relies on
fact that exit count of outer loops cannot rely on exiting blocks of
inner loops, which is true in current implementation of backedge taken count
calculation but is wrong in general. As result, when we only forget the loop that
we have just unrolled, we may still have cached data for its outer loops (in particular,
exit counts) which keeps references on blocks of inner loop that could have been
changed or even deleted.
The attached test demonstrates a situaton when after unrolling of innermost loop
the outermost loop contains a dangling pointer on non-existant block. The problem
shows up when we apply patch https://reviews.llvm.org/D44677 that makes SCEV
smarter about exit count calculation. I am not sure if the bug exists without this patch,
it appears that now it is accidentally correct just because in practice exact backedge
taken count for outer loops with complex control flow inside is never calculated.
But when SCEV learns to do so, this problem shows up.
This patch replaces existing logic of SCEV loop invalidation with a correct one, which
happens to be invalidation of outermost loop (which also leads to invalidation of all
loops inside of it). It is the only way to ensure that no outer loop keeps dangling pointers
on removed blocks, or just outdated information that has changed after unrolling.
Differential Revision: https://reviews.llvm.org/D44818
Reviewed By: samparker
llvm-svn: 328483
This broke Chromium (see crbug.com/825748). It looks like mstorsjo's follow-up
patch at D44876 fixes this, but let's revert back to green for now until that's
ready to land.
(Also reverts r328443.)
> Both GCC and MSVC only look at the low byte of a boolean when it is
> passed.
llvm-svn: 328482
CanBeMin is currently used which will report true for any unknown
values, but often a check is performed outside the loop which covers
this situation:
for (int i = 0; i < N; ++i)
...
if (N > 0)
for (int i = 0; i < N; ++i)
...
So I've add 'LoopGuardedAgainstMin' which reports whether N is
greater than the minimum value which then allows loop with a variable
loop count to be optimised. I've also moved the increasing bound
checking into its own function and replaced SumCanReachMax is another
isLoopEntryGuardedByCond function.
llvm-svn: 328480
Strictly in a conversion operator's type, a <template-param> refers to a
<template-arg> that is further ahead in the mangled name. Instead of
doing a second parse to resolve these, introduce a
ForwardTemplateReference Node and back-patch the referenced
<template-arg> when we're in the right context.
This is also a correctness fix, previously we would only do a second
parse if the <template-param> was out of bounds in the current set of
<template-args>. This lead to misdemangles (gasp!) when the conversion
operator was a member of a templated struct, for instance.
llvm-svn: 328464
Rather than eagerly propagating up parameter pack sizes in Node ctors,
find the parameter pack size during printing. This is being done to
support back-patching forward referencing <template-param>s.
llvm-svn: 328463
This patch throws a fatal error if an instregex entry doesn't actually match any instructions. This is part of the work to reduce the compile time impact of increased instregex usage (PR35955), although the x86 models seem to be relatively clean.
All the cases I encountered have now been fixed in trunk and this will ensure they don't get reintroduced.
Differential Revision: https://reviews.llvm.org/D44687
llvm-svn: 328459
Add fdiv costs for Goldmont using table 16-17 of the Intel Optimization Manual. Also add overrides for FSQRT for Goldmont and Silvermont.
Reviewers: RKSimon
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D44644
llvm-svn: 328451
We have thorough coverage of predicates and scalar types,
so we just need a sampling of vector tests to show that
things are working or not with vectors types.
llvm-svn: 328449
