On 4/22/23 14:57, Roger Sayle wrote:
This patch adds a pair of define_insn patterns to the xstormy16 machine
description that provide extendhisi2 and zero_extendhisi2, i.e. 16-bit
to 32-bit sign- and zero-extension respectively. This functionality is
already synthesized during RTL expansion, but providing patterns allow
the semantics to be exposed to the RTL optimizers. To simplify things,
this patch introduces a new %h0 output format, for emitting the high_part
register name of a double-word (SImode) register pair. The actual
code generated is identical to before.
Whilst there, I also fixed the instruction lengths and formatting of
the zero_extendqihi2 pattern. Then, mostly for documentation purposes
as the 'T' constraint isn't yet implemented, I've added a "and Rx,#255"
alternative to zero_extendqihi2 that takes advantage of its efficient
instruction encoding.
This patch has been tested by building a cross-compiler to xstormy16-elf
on x86_64-pc-linux-gnu, and confirming that the new test case passes with
"make -k check-gcc". Ok for mainline?
2023-04-22 Roger Sayle <ro...@nextmovesoftware.com>
gcc/ChangeLog
* config/stormy16/stormy16.cc (xstormy16_print_operand): Add %h
format specifier to output high_part register name of SImode reg.
* config/stormy16/stormy16.md (extendhisi2): New define_insn.
(zero_extendqihi2): Fix lengths, consistent formatting and add
"and Rx,#255" alternative, for documentation purposes.
(zero_extendhisi2): New define_insn.
gcc/testsuite/ChangeLog
* gcc.target/xstormy16/extendhisi2.c: New test case.
* gcc.target/xstormy16/zextendhisi2.c: Likewise.
Does the "T" alternative ever match? AFAICT its constraint check always
fails:
(define_constraint "T"
"@internal"
;; For Rx; not implemented yet.
(match_test "0"))
No objections, but just not sure what's going on with that T constraint.
jeff
