Accomplishes what r292982 was supposed to, which ended up
only really making the necessary test changes.
This should be applied to the 4.0 branch.
Patch by Vedran Miletić <vedran@miletic.net>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293310 91177308-0d34-0410-b5e6-96231b3b80d8
* Simplify Consecutive Merge Store Candidate Search
Now that address aliasing is much less conservative, push through
simplified store merging search and chain alias analysis which only
checks for parallel stores through the chain subgraph. This is cleaner
as the separation of non-interfering loads/stores from the
store-merging logic.
When merging stores search up the chain through a single load, and
finds all possible stores by looking down from through a load and a
TokenFactor to all stores visited.
This improves the quality of the output SelectionDAG and the output
Codegen (save perhaps for some ARM cases where we correctly constructs
wider loads, but then promotes them to float operations which appear
but requires more expensive constant generation).
Some minor peephole optimizations to deal with improved SubDAG shapes (listed below)
Additional Minor Changes:
1. Finishes removing unused AliasLoad code
2. Unifies the chain aggregation in the merged stores across code
paths
3. Re-add the Store node to the worklist after calling
SimplifyDemandedBits.
4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is
arbitrary, but seems sufficient to not cause regressions in
tests.
5. Remove Chain dependencies of Memory operations on CopyfromReg
nodes as these are captured by data dependence
6. Forward loads-store values through tokenfactors containing
{CopyToReg,CopyFromReg} Values.
7. Peephole to convert buildvector of extract_vector_elt to
extract_subvector if possible (see
CodeGen/AArch64/store-merge.ll)
8. Store merging for the ARM target is restricted to 32-bit as
some in some contexts invalid 64-bit operations are being
generated. This can be removed once appropriate checks are
added.
This finishes the change Matt Arsenault started in r246307 and
jyknight's original patch.
Many tests required some changes as memory operations are now
reorderable, improving load-store forwarding. One test in
particular is worth noting:
CodeGen/PowerPC/ppc64-align-long-double.ll - Improved load-store
forwarding converts a load-store pair into a parallel store and
a memory-realized bitcast of the same value. However, because we
lose the sharing of the explicit and implicit store values we
must create another local store. A similar transformation
happens before SelectionDAG as well.
Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293184 91177308-0d34-0410-b5e6-96231b3b80d8
clang already emits this with -cl-no-signed-zeros, but codegen
doesn't do anything with it. Treat it like the other fast math
attributes, and change one place to use it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293024 91177308-0d34-0410-b5e6-96231b3b80d8
Leave early ifcvt disabled for now since there are some
shader-db regressions.
This causes some immediate improvements, but could be better.
The cost checking that the pass does is based on critical path
length for out of order CPUs which we do not want so it skips out
on many cases we want.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293016 91177308-0d34-0410-b5e6-96231b3b80d8
The sequence like this:
v_cmpx_le_f32_e32 vcc, 0, v0
s_branch BB0_30
s_cbranch_execnz BB0_30
; BB#29:
exp null off, off, off, off done vm
s_endpgm
BB0_30:
; %endif110
is likely wrong. The s_branch instruction will unconditionally jump
to BB0_30 and the skip block (exp done + endpgm) inserted for
performing the kill instruction will never be executed. This results
in a GPU hang with Star Ruler 2.
The s_branch instruction is added during the "Control Flow Optimizer"
pass which seems to re-organize the basic blocks, and we assume
that SI_KILL_TERMINATOR is always the last instruction inside a
basic block. Thus, after inserting a skip block we just go to the
next BB without looking at the subsequent instructions after the
kill, and the s_branch op is never removed.
Instead, we should remove the unconditional out branches and let
skip the two instructions if the exec mask is non-zero.
This patch fixes the GPU hang and doesn't introduce any regressions
with "make check".
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99019
Patch by Samuel Pitoiset <samuel.pitoiset@gmail.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292985 91177308-0d34-0410-b5e6-96231b3b80d8
Regalloc creates COPY instructions which do not formally use VALU.
That results in v_mov instructions displaced after exec mask modification.
One pass which do it is SIOptimizeExecMasking, but potentially it can be
done by other passes too.
This patch adds a pass immediately after regalloc to add implicit exec
use operand to all VGPR copy instructions.
Differential Revision: https://reviews.llvm.org/D28874
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292956 91177308-0d34-0410-b5e6-96231b3b80d8
Fixes turning a 32-bit scalar load into an extending vector load
for AMDGPU when dynamically indexing a vector.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292842 91177308-0d34-0410-b5e6-96231b3b80d8
The same control register controls both, and are set to
the same defaults. Keep the old names around as aliases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292837 91177308-0d34-0410-b5e6-96231b3b80d8
Inline spiller can decide to move a spill as early as possible in the basic block.
It will skip phis and label, but we also need to make sure it skips instructions
in the basic block prologue which restore exec mask.
Added isPositionLike callback in TargetInstrInfo to detect instructions which
shall be skipped in addition to common phis, labels etc.
Differential Revision: https://reviews.llvm.org/D27997
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292554 91177308-0d34-0410-b5e6-96231b3b80d8
For -(x + y) -> (-x) + (-y), if x == -y, this would
change the result from -0.0 to 0.0. Since the fma/fmad
combine is an extension of this problem it also
applies there.
fmul should be fine, and I don't think any of the unary
operators or conversions should be a problem either.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292473 91177308-0d34-0410-b5e6-96231b3b80d8