As detailed on PR45974 and D79987, getFauxShuffleMask is creating nodes on the fly to create shuffles with inputs the same size as the result, causing problems for hasOneUse() checks in later simplification stages.
Currently only combineX86ShufflesRecursively benefits from these widened inputs so I've begun moving the functionality there, and out of getFauxShuffleMask. This allows us to remove the widening from VBROADCAST and *EXTEND* faux shuffle cases.
This just leaves the INSERT_SUBVECTOR case in getFauxShuffleMask still creating nodes, which will require more extensive refactoring.
In some cases ScheduleDAGRRList has to add new nodes to resolve problems
with interfering physical registers. When new nodes are added, it
completely re-computes the topological order, which can take a long
time, but is unnecessary. We only add nodes one by one, and initially
they do not have any predecessors. So we can just insert them at the end
of the vector. Later we add predecessors, but the helper function
properly updates the topological order much more efficiently. With this
change, the compile time for the program below drops from 300s to 30s on
my machine.
define i11129 @test1() {
%L1 = load i11129, i11129* undef
%B30 = ashr i11129 %L1, %L1
store i11129 %B30, i11129* undef
ret i11129 %L1
}
This should be generally beneficial, as we can skip a large amount of
work. Theoretically there are some scenarios where we might not safe
much, e.g. when we add a dependency between the first and last node.
Then we would have to shift all nodes. But we still do not have to spend
the time re-computing the initial order.
Reviewers: MatzeB, atrick, efriedma, niravd, paquette
Reviewed By: paquette
Differential Revision: https://reviews.llvm.org/D59722
We already had a DAG combine for (mmx (bitconvert (i64 (extractelement v2i64))))
to MOVDQ2Q.
Remove patterns for MMX_MOVQ2DQrr/MMX_MOVDQ2Qrr that use
scalar_to_vector/extractelement involving i64 scalar type with
v2i64 and x86mmx.
This code was repeated in two callers of CommitTargetLoweringOpt.
But CommitTargetLoweringOpt is also called from TargetLowering.
We should print a message for those calls to. So sink the
repeated code into CommitTargetLoweringOpt to catch those calls.
As noticed by dblaikie.
I don't know what code paths using reportError can cause stdout output
to be interleaved with stderr, so no test is added now.
Also drop an unneeded use of errs().fflush() in reportWarning().
I requested this in D64165.
The instruction is defined to only produce high result if both
destinations are the same. We can exploit this to avoid
unnecessarily clobbering a register.
In order to hide this from register allocation we use a pseudo
instruction and expand the result during MCInst creation.
Differential Revision: https://reviews.llvm.org/D80500
-Replace some ifs that should be impossible with asserts.
-Use X86::AddrDisp and X86::AddrNumOperands to make code more readable
-Use X86II::isKMasked/isKMergeMasked to do some operand skipping to remove or simplify switches
rG7873376bb36b fixes a build failure for allyesconfig.
The problem happened when the single exiting block doesn't dominate the
loop latch, then the immediate dominator of the exit block should not be
the exiting block after unrolling. As the exiting block of
different unrolled iteration can branch to the exit block, and the ith
exiting block doesn't dominate (i+1)th exiting block, the immediate
dominator of the exit block should not the nearest common dominator of
the exiting block and the loop latch of the same iteration.
Differential Revision: https://reviews.llvm.org/D80477
Currently, BasicAA does not exploit information about value ranges of
indexes. For example, consider the 2 pointers %a = %base and
%b = %base + %stride below, assuming they are used to access 4 elements.
If we know that %stride >= 4, we know the accesses do not alias. If
%stride is a constant, BasicAA currently gets that. But if the >= 4
constraint is encoded using an assume, it misses the NoAlias.
This patch extends DecomposedGEP to include an additional MinOtherOffset
field, which tracks the constant offset similar to the existing
OtherOffset, which the difference that it also includes non-negative
lower bounds on the range of the index value. When checking if the
distance between 2 accesses exceeds the access size, we can use this
improved bound.
For now this is limited to using non-negative lower bounds for indices,
as this conveniently skips cases where we do not have a useful lower
bound (because it is not constrained). We potential miss out in cases
where the lower bound is constrained but negative, but that can be
exploited in the future.
Reviewers: sanjoy, hfinkel, reames, asbirlea
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D76194
We are calling getValidShiftAmountConstant first followed by getValidMinimumShiftAmountConstant/getValidMaximumShiftAmountConstant if that failed. But both are used in the same way in ComputeNumSignBits and the Min/Max variants call getValidShiftAmountConstant internally anyhow.
Treat it as callee-saved, and always back it up. When windows code calls
entry points in unix code, marked with the windows calling convention,
that unix code can call other functions that isn't compiled with
-ffixed-x18 which may clobber x18 freely. By backing it up and restoring
it on return, we preserve the register across the function call,
fulfilling this part of the windows calling convention on another OS.
This isn't enough for making sure that x18 is preseved when non-windows
code does a callback to windows code, but is a clear improvement over
the current status quo. Additionally, wine is nowadays building many
modules as PE DLLs, which avoids the callback issue altogether for those
DLLs.
Differential Revision: https://reviews.llvm.org/D61892
This patch adds support for emission of following DWARFv5 macro
forms in .debug_macro.dwo section:
- DW_MACRO_start_file
- DW_MACRO_end_file
- DW_MACRO_define_strx
- DW_MACRO_undef_strx
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D78866
Last we looked at this and couldn't come up with a reason to change
it, but with a pragma for full loop unrolling we bypass every other
loop unroll and then fail to fully unroll a loop when the pragma is set.
Move the OnlyWhenForced out of the check and into the initialization
of the full unroll pass in the new pass manager. This doesn't show up
with the old pass manager.
Add a new option to opt so that we can turn off loop unrolling
manually since this is a difference between clang and opt.
Tested with check-clang and check-llvm.
This is a custom inserter because it was less work than teaching
tablegen a way to indicate that it is sometimes OK to have a no side
effect instruction in the output of a side effecting pattern.
The asm is needed to look like a read of the mode register to prevent
it from being deleted. However, there seems to be a bug where the mode
register def instructions are moved across the asm sideeffect by the
post-RA scheduler.
Another oddity is the immediate is formatted differently between
s_denorm_mode and s_round_mode.