diff options
author | Hans-Peter Nilsson <hp@axis.com> | 2020-01-27 04:24:59 +0100 |
---|---|---|
committer | Hans-Peter Nilsson <hp@axis.com> | 2020-05-09 03:43:51 +0200 |
commit | e49cee5c8dce341f688741e5b093f6b5560c8090 (patch) | |
tree | 5bac190390374e2d6228d73eb194990f89973675 /gcc/config | |
parent | a4f15e7ae10e2ac5f3baa4c1d5e16801e5967c18 (diff) |
cris.md: Post-reload, split/generate clobberless memory destination moves
In preparation for compare-elimination (for it to be obviously
useful), we have to have some common insn in-between that
doesn't clobber condition-codes. A move to memory is an obvious
choice. Note the FIXME: we can do this for a zero source too;
later.
gcc:
* config/cris/cris.md ("movsi"): For memory destination
post-reload, generate clobberless variant.
("*mov_tomem<mode>_split"): New split.
("*mov_tomem<mode>"): New insn.
("enabled", mov_tomem_enabled): Define and use to exclude "x" ->
"Q>m" for less-than-SImode.
Diffstat (limited to 'gcc/config')
-rw-r--r-- | gcc/config/cris/cris.md | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/gcc/config/cris/cris.md b/gcc/config/cris/cris.md index 0b42197a9f4..3de2f5a136f 100644 --- a/gcc/config/cris/cris.md +++ b/gcc/config/cris/cris.md @@ -147,6 +147,7 @@ (not (match_test "dead_or_set_regno_p (insn, CRIS_SRP_REGNUM)"))) (nil) (nil)]) +(define_attr "enabled" "no,yes" (const_string "yes")) ;; Iterator definitions. @@ -445,6 +446,15 @@ && operands[1] != const0_rtx && can_create_pseudo_p ()) operands[1] = force_reg (SImode, operands[1]); + + /* At post-reload time, we'll get here for e.g. split multi-mode insns + with a memory destination. Go directly to the clobber-less variant. + FIXME: Also applies to zero source. */ + if (MEM_P (operands[0]) && reload_completed) + { + emit_insn (gen_rtx_SET (operands[0], operands[1])); + DONE; + } }) (define_insn "*movsi_internal" @@ -650,6 +660,43 @@ move %1,%0 move %1,%0" [(set_attr "slottable" "yes,yes,yes,yes,yes,no,no,no,yes,yes,yes,no,yes,no")]) + +;; Post-reload, for memory destinations, split the clobber-variant and +;; get rid of the clobber. + +(define_split ;; "*mov_tomem<mode>_split" + [(set (match_operand:BWD 0 "memory_operand") + (match_operand:BWD 1 "nonmemory_operand")) + (clobber (reg:CC CRIS_CC0_REGNUM))] + "reload_completed" + [(set (match_dup 0) (match_dup 1))] + "") + +;; Exclude moving special-registers to memory from matching for +;; less-than-SImode, as they are SImode only (or actually, the size of +;; the register, but the ones free for "x" are naturally SImode; see +;; special measures taken for reload). +;; This might be a belt-and-suspenders thing, as a move from special +;; register to memory in less-than-SImode should not have made it here. + +(define_mode_attr mov_tomem_enabled + [(SI "yes,yes,yes,yes,yes,yes") + (HI "yes,yes,no,yes,yes,no") + (QI "yes,yes,no,yes,yes,no")]) + +(define_insn "*mov_tomem<mode>" + [(set (match_operand:BWD 0 "memory_operand" "=Q>,Q>,Q>,m,m,m") + (match_operand:BWD 1 "nonmemory_operand" "M, r, x, M,r,x"))] + "reload_completed" + "@ + clear<m> %0 + move<m> %1,%0 + move %1,%0 + clear<m> %0 + move<m> %1,%0 + move %1,%0" + [(set_attr "slottable" "yes,yes,yes,no,no,no") + (set_attr "enabled" "<mov_tomem_enabled>")]) ;; Movem patterns. Primarily for use in function prologue and epilogue. ;; Unfortunately, movem stores R0 in the highest memory location, thus |