gnu /
gcc /
7463df5c2a454aeaec786848fd8a4551e79b71a9 [APX NDD] Support APX NDD for and insn
For NDD form AND insn, there are three splitter fixes after extending legacy
patterns.
1. APX NDD does not support high QImode registers like ah, bh, ch, dh, so for
some optimization splitters that generates highpart zero_extract for QImode
need to be prohibited under NDD pattern.
2. Legacy AND insn will use r/qm/L constraint, and a post-reload splitter will
transform it into zero_extend move. But for NDD form AND, the splitter is not
strict enough as the splitter assum such AND will have the const_int operand
matching the constraint "L", then NDD form AND allows const_int with any QI
values. Restrict the splitter condition to match "L" constraint that strictly
matches zero-extend sematic.
3. Legacy AND insn will adopt r/0/Z constraint, a splitter will try to optimize
such form into strict_lowpart QImode AND when 7th bit is not set. But the
splitter will wronly convert non-zext form of NDD and with memory src, then the
strict_lowpart transform matches alternative 1 of *<code><mode>_slp_1 and
generates *movstrict<mode>_1 so the zext sematic was omitted. This could cause
highpart of dest not cleared and generates wrong code. Disable the splitter
when NDD adopted and operands[0] and operands[1] are not equal.
gcc/ChangeLog:
* config/i386/i386.md (and<mode>3): Add NDD alternatives and adjust
output template.
(*anddi_1): Likewise.
(*and<mode>_1): Likewise.
(*andqi_1): Likewise.
(*andsi_1_zext): Likewise.
(*anddi_2): Likewise.
(*andsi_2_zext): Likewise.
(*andqi_2_maybe_si): Likewise.
(*and<mode>_2): Likewise.
(*and<dwi>3_doubleword): Add NDD alternative, adopt '&' to NDD dest and
emit move for optimized case if operands[0] not equal to operands[1].
(define_split for QI highpart AND): Prohibit splitter to split NDD
form AND insn to <any_logic:code>qi_ext<mode>_3.
(define_split for QI strict_lowpart optimization): Prohibit splitter to
split NDD form AND insn to *<code><mode>3_1_slp.
(define_split for zero_extend and optimization): Prohibit splitter to
split NDD form AND insn to zero_extend insn.
gcc/testsuite/ChangeLog:
* gcc.target/i386/apx-ndd.c: Add and test.
2 files changed
