If we have a BUILD_VECTOR that is mostly a constant splat, it is often better to splat that constant then insertelement the non-constant lanes instead of insertelementing every lane from an undef base.
llvm-svn: 163304
Now that it is possible to dynamically tie MachineInstr operands,
predicated instructions are possible in SSA form:
%vreg3<def> = SUBri %vreg1, -2147483647, pred:14, pred:%noreg, %opt:%noreg
%vreg4<def,tied1> = MOVCCr %vreg3<tied0>, %vreg1, %pred:12, pred:%CPSR
Becomes a predicated SUBri with a tied imp-use:
SUBri %vreg1, -2147483647, pred:13, pred:%CPSR, opt:%noreg, %vreg1<imp-use,tied0>
This means that any instruction that is safe to move can be folded into
a MOVCC, and the *CC pseudo-instructions are no longer needed.
The test case changes reflect that Thumb2SizeReduce recognizes the
predicated instructions. It didn't understand the pseudos.
llvm-svn: 163274
Previous patch accidentally decided it couldn't convert a VFP to a
NEON instruction after it had already destroyed the old one. Not a
good move.
llvm-svn: 163230
This patch corrects the definition of umlal/smlal instructions and adds support
for matching them to the ARM dag combiner.
Bug 12213
Patch by Yin Ma!
llvm-svn: 163136
MatchInstructionImpl() function.
These values are used by the ConvertToMCInst() function to index into the
ConversionTable. The values are also needed to call the GetMCInstOperandNum()
function.
llvm-svn: 163101
For example, the ARM target does not have efficient ISel handling for vector
selects with scalar conditions. This patch adds a TLI hook which allows the
different targets to report which selects are supported well and which selects
should be converted to CF duting codegen prepare.
llvm-svn: 163093
NEON domain conversion was too heavy-handed with its widened
registers, which could have stripped existing instructions of their
dependency, leaving them vulnerable to scheduling errors.
llvm-svn: 163070
I have tested the fix, but have not been successfull in generating
a robust unit test. This can only be exposed through particular
register assignments.
llvm-svn: 162821
This wasn't the right way to enforce ordering of atomics.
We are already setting the isVolatile bit on memory operands of atomic
operations which is good enough to enforce the correct ordering.
llvm-svn: 162732
It is not safe to use normal LDR instructions because they may be
reordered by the scheduler. The ATOMIC_LDR pseudos have a mayStore flag
that prevents reordering.
Atomic loads are also prevented from participating in rematerialization
and load folding.
llvm-svn: 162713
It's not clear that they should be marked as such, but tbb formation
fails if t2LEApcrelJT is hoisted of of a loop.
This doesn't change the flags on these instructions,
UnmodeledSideEffects was already inferred from the missing pattern.
llvm-svn: 162603
The ARM BL and BLX instructions don't have predicate operands, but the
thumb variants tBL and tBLX do.
The argument registers should be added as implicit uses.
llvm-svn: 162593
