| Message ID | 92692f27-76e3-ce45-bc25-95b9a7d2b64f@yahoo.co.jp |
|---|---|
| State | New |
| Headers | show |
| Series | [1/2] xtensa: Tune "*btrue" insn pattern | expand |
On Wed, Jan 11, 2023 at 8:26 PM Takayuki 'January June' Suwa <jjsuwa_sys3175@yahoo.co.jp> wrote: > > This branch instruction has short encoding if EQ/NE comparison against > immediate zero when the Code Density Option is enabled, but its "length" > attribute was only for normal encoding. This patch fixes it. > > This patch also prevents undesireable replacement the comparison immediate > zero of the instruction (short encoding, as mentioned above) with a > register that has value of zero (normal encoding) by the postreload pass. > > gcc/ChangeLog: > > * config/xtensa/xtensa.md (*btrue): > Correct value of the attribute "length" that depends on > TARGET_DENSITY and operands, and add '?' character to the register > constraint of the compared operand. > --- > gcc/config/xtensa/xtensa.md | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) Regtested for target=xtensa-linux-uclibc, no new regressions. Committed to master.
diff --git a/gcc/config/xtensa/xtensa.md b/gcc/config/xtensa/xtensa.md index db1d68ee658..b4989832169 100644 --- a/gcc/config/xtensa/xtensa.md +++ b/gcc/config/xtensa/xtensa.md @@ -1679,7 +1679,7 @@ [(set (pc) (if_then_else (match_operator 3 "branch_operator" [(match_operand:SI 0 "register_operand" "r,r") - (match_operand:SI 1 "branch_operand" "K,r")]) + (match_operand:SI 1 "branch_operand" "K,?r")]) (label_ref (match_operand 2 "" "")) (pc)))] "" @@ -1688,7 +1688,14 @@ } [(set_attr "type" "jump,jump") (set_attr "mode" "none") - (set_attr "length" "3,3")]) + (set (attr "length") + (if_then_else (match_test "TARGET_DENSITY + && CONST_INT_P (operands[1]) + && INTVAL (operands[1]) == 0 + && (GET_CODE (operands[3]) == EQ + || GET_CODE (operands[3]) == NE)") + (const_int 2) + (const_int 3)))]) (define_insn "*ubtrue" [(set (pc)