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
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
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.
llvm-svn: 162061
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.
llvm-svn: 161994
When predicating this instruction:
Rd = ADD Rn, Rm
We need an extra operand to represent the value given to Rd when the
predicate is false:
Rd = ADDCC Rfalse, Rn, Rm, pred
The Rd and Rfalse operands are different registers while in SSA form.
Rfalse is tied to Rd to make sure they get the same register during
register allocation.
Previously, Rd and Rn were tied, but that is not required.
Compare to MOVCC:
Rd = MOVCC Rfalse, Rtrue, pred
llvm-svn: 161955
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: 161581
Function argument registers are added to the call SDNode, but
InstrEmitter now knows how to make those operands implicit, and the call
instruction doesn't have to be variadic.
Explicit register operands should only be those that are encoded in the
instruction, implicit register operands are for extra dependencies like
call argument and return values.
llvm-svn: 160188
There are patterns to handle immediates when they fit in the immediate field.
e.g. %sub = add i32 %x, -123
=> sub r0, r0, #123
Add patterns to catch immediates that do not fit but should be materialized
with a single movw instruction rather than movw + movt pair.
e.g. %sub = add i32 %x, -65535
=> movw r1, #65535
sub r0, r0, r1
rdar://11726136
llvm-svn: 159057
As an example of how the custom DiagnosticType can be used to provide
better operand-mismatch diagnostics, add a custom diagnostic for
the imm0_15 operand class used for several system instructions.
Update the tests to expect the improved diagnostic.
rdar://8987109
llvm-svn: 159051
boolean flag to an enum: { Fast, Standard, Strict } (default = Standard).
This option controls the creation by optimizations of fused FP ops that store
intermediate results in higher precision than IEEE allows (E.g. FMAs). The
behavior of this option is intended to match the behaviour specified by a
soon-to-be-introduced frontend flag: '-ffuse-fp-ops'.
Fast mode - allows formation of fused FP ops whenever they're profitable.
Standard mode - allow fusion only for 'blessed' FP ops. At present the only
blessed op is the fmuladd intrinsic. In the future more blessed ops may be
added.
Strict mode - allow fusion only if/when it can be proven that the excess
precision won't effect the result.
Note: This option only controls formation of fused ops by the optimizers. Fused
operations that are explicitly requested (e.g. FMA via the llvm.fma.* intrinsic)
will always be honored, regardless of the value of this option.
Internally TargetOptions::AllowExcessFPPrecision has been replaced by
TargetOptions::AllowFPOpFusion.
llvm-svn: 158956
This patch adds DAG combines to form FMAs from pairs of FADD + FMUL or
FSUB + FMUL. The combines are performed when:
(a) Either
AllowExcessFPPrecision option (-enable-excess-fp-precision for llc)
OR
UnsafeFPMath option (-enable-unsafe-fp-math)
are set, and
(b) TargetLoweringInfo::isFMAFasterThanMulAndAdd(VT) is true for the type of
the FADD/FSUB, and
(c) The FMUL only has one user (the FADD/FSUB).
If your target has fast FMA instructions you can make use of these combines by
overriding TargetLoweringInfo::isFMAFasterThanMulAndAdd(VT) to return true for
types supported by your FMA instruction, and adding patterns to match ISD::FMA
to your FMA instructions.
llvm-svn: 158757
The NOP, WFE, WFI, SEV and YIELD instructions are all hints w/
a different immediate value in bits [7,0]. Define a generic HINT
instruction and refactor NOP, WFI, WFI, SEV and YIELD to be
assembly aliases of that.
rdar://11600518
llvm-svn: 158674
We turned off the CMN instruction because it had semantics which we weren't
getting correct. If we are comparing with an immediate, then it's okay to use
the CMN instruction.
<rdar://problem/7569620>
llvm-svn: 158302
We handle struct byval by inserting a pseudo op, which will be expanded to a
loop at ExpandISelPseudos.
A separate patch for clang will be submitted to enable struct byval.
rdar://9877866
llvm-svn: 157793
When an instruction match is found, but the subtarget features it
requires are not available (missing floating point unit, or thumb vs arm
mode, for example), issue a diagnostic that identifies what the feature
mismatch is.
rdar://11257547
llvm-svn: 155499
predicates.
Also remove NEON2 since it's not really useful and it is confusing. If
NEON + VFP4 implies NEON2 but NEON2 doesn't imply NEON + VFP4, what does it
really mean?
rdar://10139676
llvm-svn: 154480
1. The new instruction itinerary entries are not properly described.
2. The asm parser can't handle vfms and vfnms.
3. There were no assembler, disassembler test cases.
4. HasNEON2 has the wrong assembler predicate.
rdar://10139676
llvm-svn: 154456
After register masks were introdruced to represent the call clobbers, it
is no longer necessary to have duplicate instruction for iOS.
llvm-svn: 154209
We had special instructions for iOS because r9 is call-clobbered, but
that is represented dynamically by the register mask operands now, so
there is no need for the pseudo-instructions.
llvm-svn: 154144
A MOVCCr instruction can be commuted by inverting the condition. This
can help reduce register pressure and remove unnecessary copies in some
cases.
<rdar://problem/11182914>
llvm-svn: 154033
Bob Wilson