Summary:
c.cond.fmt has been replaced by cmp.cond.fmt. Where c.cond.fmt wrote to
dedicated condition registers, cmp.cond.fmt writes 1 or 0 to normal FGR's
(like the GPR comparisons).
mov[fntz] have been replaced by seleqz and selnez. These instructions
conditionally zero a register based on a bool in a GPR. The results can
then be or'd together to act as a select without, for example, requiring a third
register read port.
mov[fntz].[ds] have been replaced with sel.[ds]
MIPS64r6 currently generates unnecessary sign-extensions for most selects.
This is because the result of a SETCC is currently an i32. Bits 32-63 are
undefined in i32 and the behaviour of seleqz/selnez would otherwise depend
on undefined bits. Later, we will fix this by making the result of SETCC an
i64 on MIPS64 targets.
Depends on D3958
Reviewers: jkolek, vmedic, zoran.jovanovic
Reviewed By: vmedic, zoran.jovanovic
Differential Revision: http://reviews.llvm.org/D4003
llvm-svn: 210777
The SelectionDAG bad a special case for ISD::SELECT_CC, where it would
allow targets to specify:
setOperationAction(ISD::SELECT_CC, MVT::Other, Expand);
to indicate that they wanted to expand ISD::SELECT_CC for all types.
This wasn't applied correctly everywhere, and it makes writing new
DAG patterns with ISD::SELECT_CC difficult.
llvm-svn: 210541
Daniel Sanders