The expression based expansion too often results in IR level optimizations
splitting the intermediate values into separate basic blocks, preventing
the formation of the VBSL instruction as the code author intended. In
particular, LICM would often hoist part of the computation out of a loop.
rdar://11011471
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164340 91177308-0d34-0410-b5e6-96231b3b80d8
A PHI can't create interference on its own. If two live ranges interfere
at a PHI, they must also interfere when leaving one of the PHI
predecessors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164330 91177308-0d34-0410-b5e6-96231b3b80d8
A common coalescing conflict in vector code is lane insertion:
%dst = FOO
%src = BAR
%dst:ssub0 = COPY %src
The live range of %src interferes with the ssub0 lane of %dst, but that
lane is never read after %src would have clobbered it. That makes it
safe to merge the live ranges and eliminate the COPY:
%dst = FOO
%dst:ssub0 = BAR
This patch teaches the new coalescer to resolve conflicts where dead
vector lanes would be clobbered, at least as long as the clobbered
vector lanes don't escape the basic block.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164250 91177308-0d34-0410-b5e6-96231b3b80d8
aligned address. Based on patch by David Peixotto.
Also use vld1.64 / vst1.64 with 128-bit alignment to take advantage of alignment
hints. rdar://12090772, rdar://12238782
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164089 91177308-0d34-0410-b5e6-96231b3b80d8
Add LIS::pruneValue() and extendToIndices(). These two functions are
used by the register coalescer when merging two live ranges requires
more than a trivial value mapping as supported by LiveInterval::join().
The pruneValue() function can remove the part of a value number that is
going to conflict in join(). Afterwards, extendToIndices can restore the
live range, using any new dominating value numbers and updating the SSA
form.
Use this complex value mapping to support merging a register into a
vector lane that has a conflicting value, but the clobbered lane is
undef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164074 91177308-0d34-0410-b5e6-96231b3b80d8
SelectionDAG::getConstantFP(double Val, EVT VT, bool isTarget);
should not be used when Val is not a simple constant (as the comment in
SelectionDAG.h indicates). This patch avoids using this function
when folding an unknown constant through a bitcast, where it cannot be
guaranteed that Val will be a simple constant.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163703 91177308-0d34-0410-b5e6-96231b3b80d8
The ARM backend can eliminate cmp instructions by reusing flags from a
nearby sub instruction with similar arguments.
Don't do that if the sub is predicated - the flags are not written
unconditionally.
<rdar://problem/12263428>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163535 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163304 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163274 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163230 91177308-0d34-0410-b5e6-96231b3b80d8
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!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163136 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163093 91177308-0d34-0410-b5e6-96231b3b80d8
Thumb2 instructions are mostly constrained to rGPR, not tGPR which is
for Thumb1.
rdar://problem/12203728
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162968 91177308-0d34-0410-b5e6-96231b3b80d8
because it does not support CMOV of vectors. To implement this efficientlyi, we broadcast the condition bit and use a sequence of NAND-OR
to select between the two operands. This is the same sequence we use for targets that don't have vector BLENDs (like SSE2).
rdar://12201387
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162926 91177308-0d34-0410-b5e6-96231b3b80d8
IR that hasn't been through SimplifyCFG can look like this:
br i1 %b, label %r, label %r
Make sure we don't create duplicate Machine CFG edges in this case.
Fix the machine code verifier to accept conditional branches with a
single CFG edge.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162230 91177308-0d34-0410-b5e6-96231b3b80d8
Add these transformations to the existing add/sub ones:
(and (select cc, -1, c), x) -> (select cc, x, (and, x, c))
(or (select cc, 0, c), x) -> (select cc, x, (or, x, c))
(xor (select cc, 0, c), x) -> (select cc, x, (xor, x, c))
The selects can then be transformed to a single predicated instruction
by peephole.
This transformation will make it possible to eliminate the ISD::CAND,
COR, and CXOR custom DAG nodes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162176 91177308-0d34-0410-b5e6-96231b3b80d8
PEI can't handle the pseudo-instructions. This can be removed when the
pseudo-instructions are replaced by normal predicated instructions.
Fixes PR13628.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162130 91177308-0d34-0410-b5e6-96231b3b80d8
It is not my plan to duplicate the entire ARM instruction set with
predicated versions. We need a way of representing predicated
instructions in SSA form without requiring a separate opcode.
Then the pseudo-instructions can go away.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162061 91177308-0d34-0410-b5e6-96231b3b80d8
Without fastcc support, the caller just falls through to CallingConv::C
for fastcc, but callee still uses fastcc, this inconsistency of calling
convention is a problem, and fastcc support can fix it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162013 91177308-0d34-0410-b5e6-96231b3b80d8
The ARM select instructions are just predicated moves. If the select is
the only use of an operand, the instruction defining the operand can be
predicated instead, saving one instruction and decreasing register
pressure.
This implementation can turn AND/ORR/EOR instructions into their
corresponding ANDCC/ORRCC/EORCC variants. Ideally, we should be able to
predicate any instruction, but we don't yet support predicated
instructions in SSA form.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161994 91177308-0d34-0410-b5e6-96231b3b80d8
reversed. This leads to wrong codegen for float-to-half conversion
intrinsics which are used to support storage-only fp16 type.
NEON variants of same instructions are fine.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161907 91177308-0d34-0410-b5e6-96231b3b80d8
and allow some optimizations to turn conditional branches into unconditional.
This commit adds a simple control-flow optimization which merges two consecutive
basic blocks which are connected by a single edge. This allows the codegen to
operate on larger basic blocks.
rdar://11973998
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161852 91177308-0d34-0410-b5e6-96231b3b80d8
