Clang is now providing intrinsics for these and so we need to support them
in the backend. Radar 8068427.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121902 91177308-0d34-0410-b5e6-96231b3b80d8
Use the same COPY_TO_REGCLASS approach as for the 2-register *_sfp instructions.
This change made a big difference in the code generated for the
CodeGen/Thumb2/cross-rc-coalescing-2.ll test: The coalescer is still doing
a fine job, but some instructions that were previously moved outside the loop
are not moved now. It's using fewer VFP registers now, which is generally
a good thing, so I think the estimates for register pressure changed and that
affected the LICM behavior. Since that isn't obviously wrong, I've just
changed the test file. This completes the work for Radar 8711675.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121730 91177308-0d34-0410-b5e6-96231b3b80d8
Jakob Olesen suggested that we can avoid the need for separate pseudo
instructions here by using COPY_TO_REGCLASS in the patterns. The pattern
gets pretty ugly but it seems to work well. Partial fix for Radar 8711675.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121718 91177308-0d34-0410-b5e6-96231b3b80d8
difficult on current ARM implementations for a few reasons.
1. Even though a single vmla has latency that is one cycle shorter than a pair
of vmul + vadd, a RAW hazard during the first (4? on Cortex-a8) can cause
additional pipeline stall. So it's frequently better to single codegen
vmul + vadd.
2. A vmla folowed by a vmul, vmadd, or vsub causes the second fp instruction to
stall for 4 cycles. We need to schedule them apart.
3. A vmla followed vmla is a special case. Obvious issuing back to back RAW
vmla + vmla is very bad. But this isn't ideal either:
vmul
vadd
vmla
Instead, we want to expand the second vmla:
vmla
vmul
vadd
Even with the 4 cycle vmul stall, the second sequence is still 2 cycles
faster.
Up to now, isel simply avoid codegen'ing fp vmla / vmls. This works well enough
but it isn't the optimial solution. This patch attempts to make it possible to
use vmla / vmls in cases where it is profitable.
A. Add missing isel predicates which cause vmla to be codegen'ed.
B. Make sure the fmul in (fadd (fmul)) has a single use. We don't want to
compute a fmul and a fmla.
C. Add additional isel checks for vmla, avoid cases where vmla is feeding into
fp instructions (except for the #3 exceptional case).
D. Add ARM hazard recognizer to model the vmla / vmls hazards.
E. Add a special pre-regalloc case to expand vmla / vmls when it's likely the
vmla / vmls will trigger one of the special hazards.
Work in progress, only A+B are enabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120960 91177308-0d34-0410-b5e6-96231b3b80d8
The only reasonable way I could find to do this is to provide an alternate
version of the addrmode6 operand with a different encoding function. Use it
for all the VLD-dup instructions for the sake of consistency.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120358 91177308-0d34-0410-b5e6-96231b3b80d8
The op11_8 field is the same for all of them so put it in the instruction
classes instead of specifying it separately for each instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120234 91177308-0d34-0410-b5e6-96231b3b80d8
'db', 'ib', 'da') instead of having that mode as a separate field in the
instruction. It's more convenient for the asm parser and much more readable for
humans.
<rdar://problem/8654088>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119310 91177308-0d34-0410-b5e6-96231b3b80d8
We could be more aggressive about making this work for a larger range of constants,
but this seems like a good start.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118201 91177308-0d34-0410-b5e6-96231b3b80d8
all of the different element sizes are pseudo instructions that map down to vext.8 underneath, with
the immediate shifted left to reflect the increased element size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118183 91177308-0d34-0410-b5e6-96231b3b80d8
