Original message:
The attached is the fix to radar://11663049. The optimization can be outlined by following rules:
(select (x != c), e, c) -> select (x != c), e, x),
(select (x == c), c, e) -> select (x == c), x, e)
where the <c> is an integer constant.
The reason for this change is that : on x86, conditional-move-from-constant needs two instructions;
however, conditional-move-from-register need only one instruction.
While the LowerSELECT() sounds to be the most convenient place for this optimization, it turns out to be a bad place. The reason is that by replacing the constant <c> with a symbolic value, it obscure some instruction-combining opportunities which would otherwise be very easy to spot. For that reason, I have to postpone the change to last instruction-combining phase.
The change passes the test of "make check-all -C <build-root/test" and "make -C project/test-suite/SingleSource".
llvm-svn: 165661
- Due to the current matching vector elements constraints in
ISD::FP_ROUND, rounding from v2f64 to v4f32 (after legalization from
v2f32) is scalarized. Add a customized v2f32 widening to convert it
into a target-specific X86ISD::VFPROUND to work around this
constraints.
llvm-svn: 165631
- Due to the current matching vector elements constraints in ISD::FP_EXTEND,
rounding from v2f32 to v2f64 is scalarized. Add a customized v2f32 widening
to convert it into a target-specific X86ISD::VFPEXT to work around this
constraints. This patch also reverts a previous attempt to fix this issue by
recovering the scalarized ISD::FP_EXTEND pattern and thus significantly
reduces the overhead of supporting non-power-2 vector FP extend.
llvm-svn: 165625
We use the enums to query whether an Attributes object has that attribute. The
opaque layer is responsible for knowing where that specific attribute is stored.
llvm-svn: 165488
a) frame setup instructions define the prologue
b) we shouldn't change our location mid-stream
Add a test to make sure that the stack adjustment stays within
the prologue.
llvm-svn: 165250
- Add 'HwEncoding' for X86 registers and call getEncodingValue() to
retrieve their encoding values.
- This's the first step to adopt new scheme. Furthur revising is onging.
llvm-svn: 165241
in the Intel syntax.
The MC layer supports emitting in the Intel syntax, but this would require the
inline assembly MachineInstr to be lowered to an MCInst before emission. This
is potential future work, but for now emitting directly from the MachineInstr
suffices.
llvm-svn: 165173
Enable the pass by default for targets that request it, and change the
-enable-early-ifcvt to the opposite -disable-early-ifcvt.
There are still some x86 regressions when enabling early if-conversion
because of the missing machine models. Disable the pass for x86 until
machine models are added.
llvm-svn: 165075
X86DAGToDAGISel::PreprocessISelDAG(), isel is moving load inside
callseq_start / callseq_end so it can be folded into a call. This can
create a cycle in the DAG when the call is glued to a copytoreg. We
have been lucky this hasn't caused too many issues because the pre-ra
scheduler has special handling of call sequences. However, it has
caused a crash in a specific tailcall case.
rdar://12393897
llvm-svn: 165072
of operand is specific to MS-style inline assembly and should not be generated
when parsing normal assembly.
The purpose of the wildcard operands are to allow the AsmParser to match
multiple instructions (i.e., MCInsts) to a given ms-style asm statement. For
the time being the matcher just returns the first match. This patch only
implements wildcard matches for memory operands. Support for register
wildcards will be added in the near future.
llvm-svn: 165057
This adds 'elf' as a recognized target triple environment value and overrides the default generated object format on Windows platforms if that value is present. This patch also enables MCJIT tests on Windows using the new environment value.
llvm-svn: 165030
map constraints and MCInst operands to inline asm operands. This replaces the
getMCInstOperandNum() function.
The logic to determine the constraints are not in place, so we still default to
a register constraint (i.e., "r"). Also, we no longer build the MCInst but
rather return just the opcode to get the MCInstrDesc.
llvm-svn: 164979
Micah Villmow