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fusion support for rmx500 #187

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94 changes: 55 additions & 39 deletions gcc/config/riscv/arcv-rmx500.md
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Original file line number Diff line number Diff line change
Expand Up @@ -20,70 +20,86 @@

(define_automaton "arcv_rmx500")

(define_cpu_unit "arcv_rmx500_ALU" "arcv_rmx500")
;(define_cpu_unit "arcv_rmx500_CSR" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_FPU" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_MPY" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_DIV" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_DMP" "arcv_rmx500")

;; Instruction reservation for arithmetic instructions.
(define_insn_reservation "arcv_rmx500_alu_arith" 3
(define_cpu_unit "arcv_rmx500_ALU_A_fuse0_early" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_ALU_A_fuse1_early" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_ALU_B_fuse0_early" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_ALU_B_fuse1_early" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_MPY32" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_DIV" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_DMP_fuse0" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_DMP_fuse1" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_fdivsqrt" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_issueA_fuse0" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_issueA_fuse1" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_issueB_fuse0" "arcv_rmx500")
(define_cpu_unit "arcv_rmx500_issueB_fuse1" "arcv_rmx500")

;; Instruction reservation for arithmetic instructions (pipe A, pipe B).
(define_insn_reservation "arcv_rmx500_alu_early_arith" 1
(and (eq_attr "tune" "arcv_rmx500")
(eq_attr "type" "unknown, const, arith, shift, slt, multi, auipc, nop,
logical, move, atomic, mvpair, bitmanip, clz, ctz, cpop,
zicond, condmove, clmul, min, max, minu, maxu"))
"arcv_rmx500_ALU, nothing*2")
(eq_attr "type" "unknown,move,const,arith,shift,slt,multi,auipc,nop,logical,\
bitmanip,min,max,minu,maxu,clz,ctz,atomic,\
condmove,mvpair,zicond,cpop,clmul"))
"((arcv_rmx500_issueA_fuse0 + arcv_rmx500_ALU_A_fuse0_early) | (arcv_rmx500_issueA_fuse1 + arcv_rmx500_ALU_A_fuse1_early)) | ((arcv_rmx500_issueB_fuse0 + arcv_rmx500_ALU_B_fuse0_early) | (arcv_rmx500_issueB_fuse1 + arcv_rmx500_ALU_B_fuse1_early))")

(define_insn_reservation "arcv_rmx500_imul_fused" 1
(and (eq_attr "tune" "arcv_rmx500")
(eq_attr "type" "imul_fused"))
"(arcv_rmx500_issueA_fuse0 + arcv_rmx500_issueA_fuse1 + arcv_rmx500_ALU_A_fuse0_early + arcv_rmx500_ALU_A_fuse1_early + arcv_rmx500_MPY32)")

(define_insn_reservation "arcv_rmx500_alu_fused" 1
(and (eq_attr "tune" "arcv_rmx500")
(eq_attr "type" "alu_fused"))
"(arcv_rmx500_issueA_fuse0 + arcv_rmx500_issueA_fuse1 + arcv_rmx500_ALU_A_fuse0_early + arcv_rmx500_ALU_A_fuse1_early) | (arcv_rmx500_issueB_fuse0 + arcv_rmx500_issueB_fuse1 + arcv_rmx500_ALU_B_fuse0_early + arcv_rmx500_ALU_B_fuse1_early)")


(define_insn_reservation "arcv_rmx500_jmp_insn" 1
(and (eq_attr "tune" "arcv_rmx500")
(eq_attr "type" "branch, jump, call, jalr, ret, trap"))
"arcv_rmx500_ALU")
(eq_attr "type" "branch,jump,call,jalr,ret,trap"))
"arcv_rmx500_issueA_fuse0 | arcv_rmx500_issueA_fuse1")

(define_insn_reservation "arcv_rmx500_div_insn" 22
(and (eq_attr "tune" "arcv_rmx500")
(eq_attr "type" "idiv"))
"arcv_rmx500_DIV*22")
"arcv_rmx500_issueA_fuse0 + arcv_rmx500_DIV, nothing*21")

(define_insn_reservation "arcv_rmx500_mpy32_insn" 10
(and (eq_attr "tune" "arcv_rmx500")
(eq_attr "type" "imul"))
"arcv_rmx500_MPY*10")
"arcv_rmx500_issueA_fuse0 + arcv_rmx500_MPY32, nothing*9")

(define_insn_reservation "arcv_rmx500_load_insn" 1
(and (eq_attr "tune" "arcv_rmx500")
(eq_attr "type" "load,fpload"))
"arcv_rmx500_DMP")
"(arcv_rmx500_issueB_fuse0 + arcv_rmx500_DMP_fuse0) | (arcv_rmx500_issueB_fuse1 + arcv_rmx500_DMP_fuse1)")

(define_insn_reservation "arcv_rmx500_store_insn" 1
(and (eq_attr "tune" "arcv_rmx500")
(eq_attr "type" "store,fpstore"))
"arcv_rmx500_DMP")
"(arcv_rmx500_issueB_fuse0 + arcv_rmx500_DMP_fuse0) | (arcv_rmx500_issueB_fuse1 + arcv_rmx500_DMP_fuse1)")

(define_insn_reservation "arcv_rmx500_farith_insn" 2
;; (soft) floating points
(define_insn_reservation "arcv_rmx500_xfer" 2
(and (eq_attr "tune" "arcv_rmx500")
(eq_attr "type" "fadd,fmul,fmadd,fcmp"))
"arcv_rmx500_FPU*2")
(eq_attr "type" "mfc,mtc,fcvt,fcvt_i2f,fcvt_f2i,fmove,fcmp"))
"(arcv_rmx500_ALU_A_fuse0_early | arcv_rmx500_ALU_B_fuse0_early), nothing")

(define_insn_reservation "arcv_rmx500_fdiv_insn" 17
(define_insn_reservation "arcv_rmx500_fmul" 2
(and (eq_attr "tune" "arcv_rmx500")
(eq_attr "type" "fdiv,fsqrt"))
"arcv_rmx500_FPU*17")
(eq_attr "type" "fadd,fmul,fmadd"))
"(arcv_rmx500_ALU_A_fuse0_early | arcv_rmx500_ALU_B_fuse0_early,nothing)")

(define_insn_reservation "arcv_rmx500_xfer" 2
(define_insn_reservation "arcv_rmx500_fdiv" 17
(and (eq_attr "tune" "arcv_rmx500")
(eq_attr "type" "fmove,mtc,mfc,fcvt,fcvt_f2i,fcvt_i2f"))
"arcv_rmx500_FPU*2")

;;(define_insn_reservation "core" 1
;; (eq_attr "type" "block, brk, dmb, flag, lr, sr, sync")
;; "arcv_rmx500_ALU0 + arcv_rmx500_ALU1 + arcv_rmx500_DMP + arcv_rmx500_MPY + arcv_rmx500_MPY64 + arcv_rmx500_DIV")
(eq_attr "type" "fdiv,fsqrt"))
"arcv_rmx500_fdivsqrt*17")

;; Bypasses
(define_bypass 9 "arcv_rmx500_mpy32_insn" "arcv_rmx500_mpy32_insn,arcv_rmx500_div_insn")

;;(define_bypass 1 "arcv_rmx500_alu_arith" "arcv_rmx500_mpy32_insn" "!accumulator_bypass_p")
(define_bypass 1 "arcv_rmx500_alu_arith,arcv_rmx500_load_insn"
"arcv_rmx500_alu_arith,arcv_rmx500_mpy32_insn,arcv_rmx500_div_insn,arcv_rmx500_load_insn")
(define_bypass 1 "arcv_rmx500_alu_arith,arcv_rmx500_load_insn"
"arcv_rmx500_store_insn" "riscv_store_data_bypass_p")
(define_bypass 1 "arcv_rmx500_alu_early_arith" "arcv_rmx500_store_insn" "riscv_store_data_bypass_p")
(define_bypass 1 "arcv_rmx500_load_insn" "arcv_rmx500_store_insn" "riscv_store_data_bypass_p")
(define_bypass 1 "arcv_rmx500_load_insn" "arcv_rmx500_alu_early_arith")
(define_bypass 1 "arcv_rmx500_load_insn" "arcv_rmx500_mpy*_insn")
(define_bypass 1 "arcv_rmx500_load_insn" "arcv_rmx500_load_insn")
(define_bypass 1 "arcv_rmx500_load_insn" "arcv_rmx500_div_insn")
(define_bypass 9 "arcv_rmx500_mpy32_insn" "arcv_rmx500_mpy*_insn")
(define_bypass 9 "arcv_rmx500_mpy32_insn" "arcv_rmx500_div_insn")
2 changes: 2 additions & 0 deletions gcc/config/riscv/riscv.cc
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Original file line number Diff line number Diff line change
Expand Up @@ -861,6 +861,7 @@ bool
arcv_micro_arch_supports_fusion_p (void)
{
return (riscv_is_micro_arch (arcv_rhx100)
|| riscv_is_micro_arch (arcv_rmx500)
|| riscv_is_micro_arch (arcv_rpx100));
}

Expand Down Expand Up @@ -11477,6 +11478,7 @@ riscv_override_options_internal (struct gcc_options *opts)
explicitly disabled.
TODO Add arcv_rmx500 once it supports fusion. */
if ((riscv_microarchitecture == arcv_rhx100
|| riscv_microarchitecture == arcv_rmx500
Comment on lines 11478 to +11481
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@MichielDerhaeg MichielDerhaeg Oct 29, 2025

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Suggested change
explicitly disabled.
TODO Add arcv_rmx500 once it supports fusion. */
if ((riscv_microarchitecture == arcv_rhx100
|| riscv_microarchitecture == arcv_rmx500
explicitly disabled. */
if ((riscv_microarchitecture == arcv_rhx100

It was decided that the mtune for rmx500 shouldn't imply the advanced fusions. They have to be explicitly turned on with the option.

|| riscv_microarchitecture == arcv_rpx100)
&& (target_flags_explicit & MASK_ARCV_ADVANCED_FUSION) == 0)
{
Expand Down
1 change: 1 addition & 0 deletions gcc/config/riscv/riscv.md
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Expand Up @@ -4948,6 +4948,7 @@
(include "corev.md")
(include "xiangshan.md")
(include "arcv-rmx100.md")
;;(include "arcv-rmx500_nf.md")
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@MichielDerhaeg MichielDerhaeg Oct 29, 2025

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Leftover?

(include "arcv-rmx500.md")
(include "arcv-rhx100.md")
(include "arcv-rpx100.md")
Expand Down