Committed with the suggested mods. Thank you for ur review, Claudiu
> -----Original Message----- > From: Andrew Burgess [mailto:andrew.burg...@embecosm.com] > Sent: Wednesday, December 14, 2016 2:01 PM > To: Claudiu Zissulescu <claudiu.zissule...@synopsys.com> > Cc: gcc-patches@gcc.gnu.org; francois.bed...@synopsys.com > Subject: Re: [PATCH 3/4] [ARC] Refurbish mul64 support. > > * Claudiu Zissulescu <claudiu.zissule...@synopsys.com> [2016-11-16 > 11:18:00 +0100]: > > > gcc/ > > 2016-07-04 Claudiu Zissulescu <claz...@synopsys.com> > > > > * config/arc/arc.md (mulsidi_600): Changed. > > (umulsidi_600): Likewise. > > (mul64): New pattern. > > (mulu64): Likewise. > > (mulsidi3): Changed. > > (umulsidi3): Likewise. > > As always the changelog description is pretty limited. Remember, it's > a _change_ log, if you mention something I already know it's changed, > better to say what has changed. Here's what I'd write for this patch: > > * config/arc/arc.md (mulsidi_600): Change to insn_and_split, > generate new mul64 insn for core multiplication work. > (umulsidi_600): Likewise, but generate mulu64 insn. > (mul64): New insn pattern, content largely taken from old > mulsidi_600 insn pattern. > (mulu64): Likewise, but content from old umulsidi_600 > pattern. > (mulsidi3): Remove move to destination, this is now handled by > mulsidi_600 insn_and_split. > (umulsidi3): Likewise, but using new umulsidi_600. > > It never hurts (I think) to include a longer description of the change > with the commit, especially when the commit should produce no user > visible change in the final result and is just a clean up. This has > two benefits I think, first, if we do ever track a bug back to this > commit (and the commit log say that no user visible changes are > expected) then we know, with 100% certainty, that this was a mistake > and not just an unfortunate side effect of an intended change. > Second, stating that no user visible changes are expected explains why > there are no tests with the patch; the assumption would be that the > functionality is already covered by existing tests. > > Here's what I'd write for this commit: > > Rework 64-bit multiplication patterns > > Previously users of mulsidi_600 and umulsidi_600 had to take > care of moving the multiplication result into the final > destination themselves (from the MUL64_OUT_REG register). > This commit converts these two instruction patterns into > insn_and_split patterns that now take the final destination as > an extra operand. The insn_and_split patterns generate the > multiplication using two new multiplication instruction > patterns, then generate the move of the result from the > MUL64_OUT_REG register into the final destination. > > This is a clean up commit, there should be no user visible > changes after this commit. > > I tend to prefer move verbose commit logs, which are not to everyones > taste, but I'm sure there's some middle ground we can find between my > ultra-verbose style and your ultra-brief style :) > > But otherwise, this looks fine. > > Thanks, > Andrew > > > > --- > > gcc/config/arc/arc.md | 64 ++++++++++++++++++++++++++++++++------- > ------------ > > 1 file changed, 40 insertions(+), 24 deletions(-) > > > > diff --git a/gcc/config/arc/arc.md b/gcc/config/arc/arc.md > > index 86de423..76a3207 100644 > > --- a/gcc/config/arc/arc.md > > +++ b/gcc/config/arc/arc.md > > @@ -12,10 +12,6 @@ > > ;; Profiling support and performance improvements by > > ;; Joern Rennecke (joern.renne...@embecosm.com) > > ;; > > -;; Support for DSP multiply instructions and mul64 > > -;; instructions for ARC600; and improvements in flag setting > > -;; instructions by > > -;; Muhammad Khurram Riaz (khurram.r...@arc.com) > > > > ;; This file is part of GCC. > > > > @@ -2011,14 +2007,26 @@ > > [(set_attr "is_sfunc" "yes") > > (set_attr "predicable" "yes")]) > > > > -(define_insn "mulsidi_600" > > +(define_insn_and_split "mulsidi_600" > > + [(set (match_operand:DI 0 "register_operand" > > "=c, c,c, > c") > > + (mult:DI (sign_extend:DI (match_operand:SI 1 "register_operand" > "%Rcq#q, c,c, c")) > > + (sign_extend:DI (match_operand:SI 2 > "nonmemory_operand" "Rcq#q,cL,L,C32")))) > > + (clobber (reg:DI MUL64_OUT_REG))] > > + "TARGET_MUL64_SET" > > + "#" > > + "TARGET_MUL64_SET" > > + [(const_int 0)] > > + "emit_insn (gen_mul64 (operands[1], operands[2])); > > + emit_move_insn (operands[0], gen_rtx_REG (DImode, > MUL64_OUT_REG)); > > + DONE;" > > + [(set_attr "type" "multi") > > + (set_attr "length" "8")]) > > + > > +(define_insn "mul64" > > [(set (reg:DI MUL64_OUT_REG) > > - (mult:DI (sign_extend:DI > > - (match_operand:SI 0 "register_operand" "%Rcq#q,c,c,c")) > > - (sign_extend:DI > > -; assembler issue for "I", see mulsi_600 > > -; (match_operand:SI 1 "register_operand" > "Rcq#q,cL,I,Cal"))))] > > - (match_operand:SI 1 "register_operand" > "Rcq#q,cL,L,C32"))))] > > + (mult:DI > > + (sign_extend:DI (match_operand:SI 0 "register_operand" "%Rcq#q, > c,c, c")) > > + (sign_extend:DI (match_operand:SI 1 "nonmemory_operand" > "Rcq#q,cL,L,C32"))))] > > "TARGET_MUL64_SET" > > "mul64%? \t0, %0, %1%&" > > [(set_attr "length" "*,4,4,8") > > @@ -2027,14 +2035,26 @@ > > (set_attr "predicable" "yes,yes,no,yes") > > (set_attr "cond" "canuse,canuse,canuse_limm,canuse")]) > > > > -(define_insn "umulsidi_600" > > +(define_insn_and_split "umulsidi_600" > > + [(set (match_operand:DI 0 "register_operand" > > "=c,c, c") > > + (mult:DI (zero_extend:DI (match_operand:SI 1 "register_operand" > "%c,c, c")) > > + (sign_extend:DI (match_operand:SI 2 > "nonmemory_operand" "cL,L,C32")))) > > + (clobber (reg:DI MUL64_OUT_REG))] > > + "TARGET_MUL64_SET" > > + "#" > > + "TARGET_MUL64_SET" > > + [(const_int 0)] > > + "emit_insn (gen_mulu64 (operands[1], operands[2])); > > + emit_move_insn (operands[0], gen_rtx_REG (DImode, > MUL64_OUT_REG)); > > + DONE;" > > + [(set_attr "type" "umulti") > > + (set_attr "length" "8")]) > > + > > +(define_insn "mulu64" > > [(set (reg:DI MUL64_OUT_REG) > > - (mult:DI (zero_extend:DI > > - (match_operand:SI 0 "register_operand" "%c,c,c")) > > - (sign_extend:DI > > -; assembler issue for "I", see mulsi_600 > > -; (match_operand:SI 1 "register_operand" "cL,I,Cal"))))] > > - (match_operand:SI 1 "register_operand" "cL,L,C32"))))] > > + (mult:DI > > + (zero_extend:DI (match_operand:SI 0 "register_operand" "%c,c,c")) > > + (zero_extend:DI (match_operand:SI 1 "nonmemory_operand" > "cL,L,C32"))))] > > "TARGET_MUL64_SET" > > "mulu64%? \t0, %0, %1%&" > > [(set_attr "length" "4,4,8") > > @@ -2098,9 +2118,7 @@ > > } > > else if (TARGET_MUL64_SET) > > { > > - operands[2] = force_reg (SImode, operands[2]); > > - emit_insn (gen_mulsidi_600 (operands[1], operands[2])); > > - emit_move_insn (operands[0], gen_rtx_REG (DImode, > MUL64_OUT_REG)); > > + emit_insn (gen_mulsidi_600 (operands[0], operands[1], operands[2])); > > DONE; > > } > > else if (TARGET_MULMAC_32BY16_SET) > > @@ -2332,9 +2350,7 @@ > > } > > else if (TARGET_MUL64_SET) > > { > > - operands[2] = force_reg (SImode, operands[2]); > > - emit_insn (gen_umulsidi_600 (operands[1], operands[2])); > > - emit_move_insn (operands[0], gen_rtx_REG (DImode, > MUL64_OUT_REG)); > > + emit_insn (gen_umulsidi_600 (operands[0], operands[1], > operands[2])); > > DONE; > > } > > else if (TARGET_MULMAC_32BY16_SET) > > -- > > 1.9.1 > >
