From 4f3ef52ec94a9ff3b9dcf325d8455881faccbd4e Mon Sep 17 00:00:00 2001
From: Alban Gruin <alban.gruin@irit.fr>
Date: Fri, 6 May 2022 13:11:30 +0200
Subject: [PATCH] issue stage: critical path improvements
Signed-off-by: Alban Gruin <alban.gruin@irit.fr>
---
include/ariane_pkg.sv | 4 +
src/decoder.sv | 9 ++
src/issue_read_operands.sv | 210 +++++++++++++++----------------------
src/issue_stage.sv | 9 --
src/scoreboard.sv | 31 +++---
5 files changed, 114 insertions(+), 149 deletions(-)
diff --git a/include/ariane_pkg.sv b/include/ariane_pkg.sv
index 290219e3..9c35b0b6 100644
--- a/include/ariane_pkg.sv
+++ b/include/ariane_pkg.sv
@@ -603,6 +603,10 @@ package ariane_pkg;
logic valid; // is the result valid
logic use_imm; // should we use the immediate as operand b?
logic use_zimm; // use zimm as operand a
+ logic use_rs1_fpr;
+ logic use_rs2_fpr;
+ logic use_imm_fpr;
+ logic use_rd_fpr;
logic use_pc; // set if we need to use the PC as operand a, PC from exception
exception_t ex; // exception has occurred
branchpredict_sbe_t bp; // branch predict scoreboard data structure
diff --git a/src/decoder.sv b/src/decoder.sv
index e0c551e7..4ea5de72 100644
--- a/src/decoder.sv
+++ b/src/decoder.sv
@@ -80,6 +80,10 @@ module decoder import ariane_pkg::*; (
instruction_o.trans_id = '0;
instruction_o.is_compressed = is_compressed_i;
instruction_o.use_zimm = 1'b0;
+ instruction_o.use_rs1_fpr = 1'b0;
+ instruction_o.use_rs2_fpr = 1'b0;
+ instruction_o.use_imm_fpr = 1'b0;
+ instruction_o.use_rd_fpr = 1'b0;
instruction_o.bp = branch_predict_i;
ecall = 1'b0;
ebreak = 1'b0;
@@ -1005,6 +1009,11 @@ module decoder import ariane_pkg::*; (
default: illegal_instr = 1'b1;
endcase
+
+ instruction_o.use_rs1_fpr = is_rs1_fpr(instruction_o.op);
+ instruction_o.use_rs2_fpr = is_rs2_fpr(instruction_o.op);
+ instruction_o.use_imm_fpr = is_imm_fpr(instruction_o.op);
+ instruction_o.use_rd_fpr = is_rd_fpr(instruction_o.op);
end
end
diff --git a/src/issue_read_operands.sv b/src/issue_read_operands.sv
index 1bdd15a8..7e6a2b27 100644
--- a/src/issue_read_operands.sv
+++ b/src/issue_read_operands.sv
@@ -26,13 +26,10 @@ module issue_read_operands import ariane_pkg::*; #(
input logic issue_instr_valid_i,
output logic issue_ack_o,
// lookup rd in scoreboard
- output logic [REG_ADDR_SIZE-1:0] rs1_o,
input riscv::xlen_t rs1_i,
input logic rs1_valid_i,
- output logic [REG_ADDR_SIZE-1:0] rs2_o,
input riscv::xlen_t rs2_i,
input logic rs2_valid_i,
- output logic [REG_ADDR_SIZE-1:0] rs3_o,
input logic [FLEN-1:0] rs3_i,
input logic rs3_valid_i,
// get clobber input
@@ -149,93 +146,36 @@ module issue_read_operands import ariane_pkg::*; #(
// ---------------
// check that all operands are available, otherwise stall
// forward corresponding register
- always_comb begin : operands_available
- stall = 1'b0;
- // operand forwarding signals
- forward_rs1 = 1'b0;
- forward_rs2 = 1'b0;
- forward_rs3 = 1'b0; // FPR only
- // poll the scoreboard for those values
- rs1_o = issue_instr_i.rs1;
- rs2_o = issue_instr_i.rs2;
- rs3_o = issue_instr_i.result[REG_ADDR_SIZE-1:0]; // rs3 is encoded in imm field
-
- // 0. check that we are not using the zimm type in RS1
- // as this is an immediate we do not have to wait on anything here
- // 1. check if the source registers are clobbered --> check appropriate clobber list (gpr/fpr)
- // 2. poll the scoreboard
- if (!issue_instr_i.use_zimm && (is_rs1_fpr(issue_instr_i.op) ? rd_clobber_fpr_i[issue_instr_i.rs1] != NONE
- : rd_clobber_gpr_i[issue_instr_i.rs1] != NONE)) begin
- // check if the clobbering instruction is not a CSR instruction, CSR instructions can only
- // be fetched through the register file since they can't be forwarded
- // if the operand is available, forward it. CSRs don't write to/from FPR
- if (rs1_valid_i && (is_rs1_fpr(issue_instr_i.op) ? 1'b1 : ((rd_clobber_gpr_i[issue_instr_i.rs1] != CSR) || (issue_instr_i.op == SFENCE_VMA)))) begin
- forward_rs1 = 1'b1;
- end else begin // the operand is not available -> stall
- stall = 1'b1;
- end
- end
+ logic is_instr_csr_or_fence_rs1, is_instr_csr_or_fence_rs2;
+ assign is_instr_csr_or_fence_rs1 = rs1_valid_i && (issue_instr_i.use_rs1_fpr || rd_clobber_gpr_i[issue_instr_i.rs1] != CSR || issue_instr_i.op == SFENCE_VMA);
+ assign is_instr_csr_or_fence_rs2 = rs2_valid_i && (issue_instr_i.use_rs2_fpr || rd_clobber_gpr_i[issue_instr_i.rs2] != CSR || issue_instr_i.op == SFENCE_VMA);
- if (is_rs2_fpr(issue_instr_i.op) ? rd_clobber_fpr_i[issue_instr_i.rs2] != NONE
- : rd_clobber_gpr_i[issue_instr_i.rs2] != NONE) begin
- // if the operand is available, forward it. CSRs don't write to/from FPR
- if (rs2_valid_i && (is_rs2_fpr(issue_instr_i.op) ? 1'b1 : ( (rd_clobber_gpr_i[issue_instr_i.rs2] != CSR) || (issue_instr_i.op == SFENCE_VMA)))) begin
- forward_rs2 = 1'b1;
- end else begin // the operand is not available -> stall
- stall = 1'b1;
- end
- end
+ logic should_forward_rs1, should_forward_rs2, should_forward_rs3;
+ assign should_forward_rs1 = !issue_instr_i.use_zimm && ((issue_instr_i.use_rs1_fpr && rd_clobber_fpr_i[issue_instr_i.rs1]) || rd_clobber_gpr_i[issue_instr_i.rs1] != NONE);
+ assign should_forward_rs2 = (issue_instr_i.use_rs2_fpr && rd_clobber_fpr_i[issue_instr_i.rs2]) || rd_clobber_gpr_i[issue_instr_i.rs2] != NONE;
+ assign should_forward_rs3 = issue_instr_i.use_imm_fpr && rd_clobber_fpr_i[issue_instr_i.result[REG_ADDR_SIZE-1:0]] != NONE;
- if (is_imm_fpr(issue_instr_i.op) && rd_clobber_fpr_i[issue_instr_i.result[REG_ADDR_SIZE-1:0]] != NONE) begin
- // if the operand is available, forward it. CSRs don't write to/from FPR so no need to check
- if (rs3_valid_i) begin
- forward_rs3 = 1'b1;
- end else begin // the operand is not available -> stall
- stall = 1'b1;
- end
- end
- end
+ assign stall = (should_forward_rs1 && !is_instr_csr_or_fence_rs1) ||
+ (should_forward_rs2 && !is_instr_csr_or_fence_rs2) ||
+ (should_forward_rs3 && !rs3_valid_i);
- // Forwarding/Output MUX
- always_comb begin : forwarding_operand_select
- // default is regfiles (gpr or fpr)
- operand_a_n = operand_a_regfile;
- operand_b_n = operand_b_regfile;
- // immediates are the third operands in the store case
- // for FP operations, the imm field can also be the third operand from the regfile
- imm_n = is_imm_fpr(issue_instr_i.op) ? {{riscv::XLEN-FLEN{1'b0}}, operand_c_regfile} : issue_instr_i.result;
- trans_id_n = issue_instr_i.trans_id;
- fu_n = issue_instr_i.fu;
- operator_n = issue_instr_i.op;
- // or should we forward
- if (forward_rs1) begin
- operand_a_n = rs1_i;
- end
-
- if (forward_rs2) begin
- operand_b_n = rs2_i;
- end
-
- if (forward_rs3) begin
- imm_n = {{riscv::XLEN-FLEN{1'b0}}, rs3_i};
- end
-
- // use the PC as operand a
- if (issue_instr_i.use_pc) begin
- operand_a_n = {{riscv::XLEN-riscv::VLEN{issue_instr_i.pc[riscv::VLEN-1]}}, issue_instr_i.pc};
- end
+ assign forward_rs1 = should_forward_rs1 && is_instr_csr_or_fence_rs1;
+ assign forward_rs2 = should_forward_rs2 && is_instr_csr_or_fence_rs2;
+ assign forward_rs3 = should_forward_rs3 && rs3_valid_i;
- // use the zimm as operand a
- if (issue_instr_i.use_zimm) begin
- // zero extend operand a
- operand_a_n = {{riscv::XLEN-5{1'b0}}, issue_instr_i.rs1[4:0]};
- end
- // or is it an immediate (including PC), this is not the case for a store and control flow instructions
- // also make sure operand B is not already used as an FP operand
- if (issue_instr_i.use_imm && (issue_instr_i.fu != STORE) && (issue_instr_i.fu != CTRL_FLOW) && !is_rs2_fpr(issue_instr_i.op)) begin
- operand_b_n = issue_instr_i.result;
- end
- end
+ // Forwarding/Output MUX
+ assign operand_a_n = (issue_instr_i.use_zimm) ? {{riscv::XLEN-5{1'b0}}, issue_instr_i.rs1[4:0]} :
+ (issue_instr_i.use_pc) ? {{riscv::XLEN-riscv::VLEN{issue_instr_i.pc[riscv::VLEN-1]}}, issue_instr_i.pc} :
+ (forward_rs1) ? rs1_i : operand_a_regfile;
+ assign operand_b_n = (issue_instr_i.use_imm && !(issue_instr_i.fu inside {STORE, CTRL_FLOW}) && !issue_instr_i.use_rs2_fpr) ? issue_instr_i.result :
+ (forward_rs2) ? rs2_i : operand_b_regfile;
+
+ assign imm_n = (forward_rs3) ? {{riscv::XLEN-FLEN{1'b0}}, rs3_i} :
+ issue_instr_i.use_imm_fpr ? {{riscv::XLEN-FLEN{1'b0}}, operand_c_regfile} :
+ issue_instr_i.result;
+ assign trans_id_n = issue_instr_i.trans_id;
+ assign fu_n = issue_instr_i.fu;
+ assign operator_n = issue_instr_i.op;
// FU select, assert the correct valid out signal (in the next cycle)
// This needs to be like this to make verilator happy. I know its ugly.
@@ -299,47 +239,65 @@ module issue_read_operands import ariane_pkg::*; #(
end
end
+ logic [NR_COMMIT_PORTS-1:0] waw_check;
+ logic rd_clobbered;
+
+ assign rd_clobbered = (issue_instr_i.use_rd_fpr && rd_clobber_fpr_i[issue_instr_i.rd] == NONE) ||
+ rd_clobber_gpr_i[issue_instr_i.rd] == NONE;
+
+ for (genvar i = 0; i < NR_COMMIT_PORTS; i++) begin
+ assign waw_check[i] = (issue_instr_i.use_rd_fpr && we_fpr_i[i] && waddr_i[i] == issue_instr_i.rd) ||
+ we_gpr_i[i] && waddr_i[i] == issue_instr_i.rd;
+ end
+
+ assign issue_ack_o = issue_instr_valid_i &&
+ (
+ (!stall && !fu_busy && (rd_clobbered || (|waw_check))) ||
+ (issue_instr_i.ex.valid) ||
+ (issue_instr_i.fu == NONE)
+ );
+
// We can issue an instruction if we do not detect that any other instruction is writing the same
// destination register.
// We also need to check if there is an unresolved branch in the scoreboard.
- always_comb begin : issue_scoreboard
- // default assignment
- issue_ack_o = 1'b0;
- // check that we didn't stall, that the instruction we got is valid
- // and that the functional unit we need is not busy
- if (issue_instr_valid_i) begin
- // check that the corresponding functional unit is not busy
- if (!stall && !fu_busy) begin
- // -----------------------------------------
- // WAW - Write After Write Dependency Check
- // -----------------------------------------
- // no other instruction has the same destination register -> issue the instruction
- if (is_rd_fpr(issue_instr_i.op) ? (rd_clobber_fpr_i[issue_instr_i.rd] == NONE)
- : (rd_clobber_gpr_i[issue_instr_i.rd] == NONE)) begin
- issue_ack_o = 1'b1;
- end
- // or check that the target destination register will be written in this cycle by the
- // commit stage
- for (int unsigned i = 0; i < NR_COMMIT_PORTS; i++)
- if (is_rd_fpr(issue_instr_i.op) ? (we_fpr_i[i] && waddr_i[i] == issue_instr_i.rd)
- : (we_gpr_i[i] && waddr_i[i] == issue_instr_i.rd)) begin
- issue_ack_o = 1'b1;
- end
- end
- // we can also issue the instruction under the following two circumstances:
- // we can do this even if we are stalled or no functional unit is ready (as we don't need one)
- // the decoder needs to make sure that the instruction is marked as valid when it does not
- // need any functional unit or if an exception occurred previous to the execute stage.
- // 1. we already got an exception
- if (issue_instr_i.ex.valid) begin
- issue_ack_o = 1'b1;
- end
- // 2. it is an instruction which does not need any functional unit
- if (issue_instr_i.fu == NONE) begin
- issue_ack_o = 1'b1;
- end
- end
- end
+ // always_comb begin : issue_scoreboard
+ // // default assignment
+ // issue_ack_o = 1'b0;
+ // // check that we didn't stall, that the instruction we got is valid
+ // // and that the functional unit we need is not busy
+ // if (issue_instr_valid_i) begin
+ // // check that the corresponding functional unit is not busy
+ // if (!stall && !fu_busy) begin
+ // // -----------------------------------------
+ // // WAW - Write After Write Dependency Check
+ // // -----------------------------------------
+ // // no other instruction has the same destination register -> issue the instruction
+ // if (is_rd_fpr(issue_instr_i.op) ? (rd_clobber_fpr_i[issue_instr_i.rd] == NONE)
+ // : (rd_clobber_gpr_i[issue_instr_i.rd] == NONE)) begin
+ // issue_ack_o = 1'b1;
+ // end
+ // // or check that the target destination register will be written in this cycle by the
+ // // commit stage
+ // for (int unsigned i = 0; i < NR_COMMIT_PORTS; i++)
+ // if (is_rd_fpr(issue_instr_i.op) ? (we_fpr_i[i] && waddr_i[i] == issue_instr_i.rd)
+ // : (we_gpr_i[i] && waddr_i[i] == issue_instr_i.rd)) begin
+ // issue_ack_o = 1'b1;
+ // end
+ // end
+ // // we can also issue the instruction under the following two circumstances:
+ // // we can do this even if we are stalled or no functional unit is ready (as we don't need one)
+ // // the decoder needs to make sure that the instruction is marked as valid when it does not
+ // // need any functional unit or if an exception occurred previous to the execute stage.
+ // // 1. we already got an exception
+ // if (issue_instr_i.ex.valid) begin
+ // issue_ack_o = 1'b1;
+ // end
+ // // 2. it is an instruction which does not need any functional unit
+ // if (issue_instr_i.fu == NONE) begin
+ // issue_ack_o = 1'b1;
+ // end
+ // end
+ // end
// ----------------------
// Integer Register File
@@ -408,8 +366,8 @@ module issue_read_operands import ariane_pkg::*; #(
end
endgenerate
- assign operand_a_regfile = is_rs1_fpr(issue_instr_i.op) ? {{riscv::XLEN-FLEN{1'b0}}, fprdata[0]} : rdata[0];
- assign operand_b_regfile = is_rs2_fpr(issue_instr_i.op) ? {{riscv::XLEN-FLEN{1'b0}}, fprdata[1]} : rdata[1];
+ assign operand_a_regfile = issue_instr_i.use_rs1_fpr ? {{riscv::XLEN-FLEN{1'b0}}, fprdata[0]} : rdata[0];
+ assign operand_b_regfile = issue_instr_i.use_rs2_fpr ? {{riscv::XLEN-FLEN{1'b0}}, fprdata[1]} : rdata[1];
assign operand_c_regfile = fprdata[2];
// ----------------------
diff --git a/src/issue_stage.sv b/src/issue_stage.sv
index cc433b38..0bdde401 100644
--- a/src/issue_stage.sv
+++ b/src/issue_stage.sv
@@ -82,15 +82,12 @@ module issue_stage import ariane_pkg::*; #(
fu_t [2**REG_ADDR_SIZE-1:0] rd_clobber_gpr_sb_iro;
fu_t [2**REG_ADDR_SIZE-1:0] rd_clobber_fpr_sb_iro;
- logic [REG_ADDR_SIZE-1:0] rs1_iro_sb;
riscv::xlen_t rs1_sb_iro;
logic rs1_valid_sb_iro;
- logic [REG_ADDR_SIZE-1:0] rs2_iro_sb;
riscv::xlen_t rs2_sb_iro;
logic rs2_valid_iro_sb;
- logic [REG_ADDR_SIZE-1:0] rs3_iro_sb;
logic [FLEN-1:0] rs3_sb_iro;
logic rs3_valid_iro_sb;
@@ -130,13 +127,10 @@ module issue_stage import ariane_pkg::*; #(
.unresolved_branch_i ( 1'b0 ),
.rd_clobber_gpr_o ( rd_clobber_gpr_sb_iro ),
.rd_clobber_fpr_o ( rd_clobber_fpr_sb_iro ),
- .rs1_i ( rs1_iro_sb ),
.rs1_o ( rs1_sb_iro ),
.rs1_valid_o ( rs1_valid_sb_iro ),
- .rs2_i ( rs2_iro_sb ),
.rs2_o ( rs2_sb_iro ),
.rs2_valid_o ( rs2_valid_iro_sb ),
- .rs3_i ( rs3_iro_sb ),
.rs3_o ( rs3_sb_iro ),
.rs3_valid_o ( rs3_valid_iro_sb ),
@@ -166,13 +160,10 @@ module issue_stage import ariane_pkg::*; #(
.issue_ack_o ( issue_ack_iro_sb ),
.fu_data_o ( fu_data_o ),
.flu_ready_i ( flu_ready_i ),
- .rs1_o ( rs1_iro_sb ),
.rs1_i ( rs1_sb_iro ),
.rs1_valid_i ( rs1_valid_sb_iro ),
- .rs2_o ( rs2_iro_sb ),
.rs2_i ( rs2_sb_iro ),
.rs2_valid_i ( rs2_valid_iro_sb ),
- .rs3_o ( rs3_iro_sb ),
.rs3_i ( rs3_sb_iro ),
.rs3_valid_i ( rs3_valid_iro_sb ),
.rd_clobber_gpr_i ( rd_clobber_gpr_sb_iro ),
diff --git a/src/scoreboard.sv b/src/scoreboard.sv
index c78897da..98719910 100644
--- a/src/scoreboard.sv
+++ b/src/scoreboard.sv
@@ -28,15 +28,12 @@ module scoreboard #(
output ariane_pkg::fu_t [2**ariane_pkg::REG_ADDR_SIZE-1:0] rd_clobber_fpr_o,
// regfile like interface to operand read stage
- input logic [ariane_pkg::REG_ADDR_SIZE-1:0] rs1_i,
output riscv::xlen_t rs1_o,
output logic rs1_valid_o,
- input logic [ariane_pkg::REG_ADDR_SIZE-1:0] rs2_i,
output riscv::xlen_t rs2_o,
output logic rs2_valid_o,
- input logic [ariane_pkg::REG_ADDR_SIZE-1:0] rs3_i,
output logic [ariane_pkg::FLEN-1:0] rs3_o,
output logic rs3_valid_o,
@@ -76,7 +73,7 @@ module scoreboard #(
} mem_q [NR_ENTRIES-1:0], mem_n [NR_ENTRIES-1:0];
logic issue_full, issue_en;
- logic [BITS_ENTRIES-1:0] issue_cnt_n, issue_cnt_q;
+ logic [BITS_ENTRIES:0] issue_cnt_n, issue_cnt_q;
logic [BITS_ENTRIES-1:0] write_pointer_n, write_pointer_q;
logic [BITS_ENTRIES-1:0] issue_pointer_n, issue_pointer_q;
logic [NR_COMMIT_PORTS-1:0][BITS_ENTRIES-1:0] commit_pointer_n, commit_pointer_q;
@@ -89,7 +86,7 @@ module scoreboard #(
// the issue queue is full don't issue any new instructions
// works since aligned to power of 2
- assign issue_full = &issue_cnt_q;
+ assign issue_full = (issue_cnt_q[BITS_ENTRIES] == 1'b1);
assign sb_full_o = issue_full;
@@ -124,7 +121,8 @@ module scoreboard #(
// decoded_instr_ack_o = 1'b1;
mem_n[write_pointer_q] = {1'b1,
1'b1, // valid bit
- ariane_pkg::is_rd_fpr(decoded_instr_i.op), // whether rd goes to the fpr
+ decoded_instr_i.use_rd_fpr,
+ // ariane_pkg::is_rd_fpr(decoded_instr_i.op), // whether rd goes to the fpr
decoded_instr_i // decoded instruction record
};
has_mem_access_n[write_pointer_q] = decoded_instr_i.fu inside {ariane_pkg::LOAD, ariane_pkg::STORE};
@@ -289,17 +287,22 @@ module scoreboard #(
logic [NR_ENTRIES+NR_WB_PORTS-1:0][riscv::XLEN-1:0] rs_data;
logic rs1_valid, rs2_valid;
+ logic [ariane_pkg::REG_ADDR_SIZE-1:0] rs1, rs2, rs3;
+ assign rs1 = issue_instr_o.rs1;
+ assign rs2 = issue_instr_o.rs2;
+ assign rs3 = issue_instr_o.result[ariane_pkg::REG_ADDR_SIZE-1:0]; // rs3 is encoded in imm field
+
// WB ports have higher prio than entries
for (genvar k = 0; unsigned'(k) < NR_WB_PORTS; k++) begin : gen_rs_wb
- assign rs1_fwd_req[k] = (mem_q[trans_id_i[k]].sbe.rd == rs1_i) & wt_valid_i[k] & (~ex_i[k].valid) & (mem_q[trans_id_i[k]].is_rd_fpr_flag == ariane_pkg::is_rs1_fpr(issue_instr_o.op));
- assign rs2_fwd_req[k] = (mem_q[trans_id_i[k]].sbe.rd == rs2_i) & wt_valid_i[k] & (~ex_i[k].valid) & (mem_q[trans_id_i[k]].is_rd_fpr_flag == ariane_pkg::is_rs2_fpr(issue_instr_o.op));
- assign rs3_fwd_req[k] = (mem_q[trans_id_i[k]].sbe.rd == rs3_i) & wt_valid_i[k] & (~ex_i[k].valid) & (mem_q[trans_id_i[k]].is_rd_fpr_flag == ariane_pkg::is_imm_fpr(issue_instr_o.op));
+ assign rs1_fwd_req[k] = (mem_q[trans_id_i[k]].sbe.rd == rs1) & wt_valid_i[k] & (~ex_i[k].valid) & (mem_q[trans_id_i[k]].is_rd_fpr_flag == issue_instr_o.use_rs1_fpr);
+ assign rs2_fwd_req[k] = (mem_q[trans_id_i[k]].sbe.rd == rs2) & wt_valid_i[k] & (~ex_i[k].valid) & (mem_q[trans_id_i[k]].is_rd_fpr_flag == issue_instr_o.use_rs2_fpr);
+ assign rs3_fwd_req[k] = (mem_q[trans_id_i[k]].sbe.rd == rs3) & wt_valid_i[k] & (~ex_i[k].valid) & (mem_q[trans_id_i[k]].is_rd_fpr_flag == issue_instr_o.use_imm_fpr);
assign rs_data[k] = wbdata_i[k];
end
for (genvar k = 0; unsigned'(k) < NR_ENTRIES; k++) begin : gen_rs_entries
- assign rs1_fwd_req[k+NR_WB_PORTS] = (mem_q[k].sbe.rd == rs1_i) & ~mem_q[k].pending & mem_q[k].issued & mem_q[k].sbe.valid & (mem_q[k].is_rd_fpr_flag == ariane_pkg::is_rs1_fpr(issue_instr_o.op));
- assign rs2_fwd_req[k+NR_WB_PORTS] = (mem_q[k].sbe.rd == rs2_i) & ~mem_q[k].pending & mem_q[k].issued & mem_q[k].sbe.valid & (mem_q[k].is_rd_fpr_flag == ariane_pkg::is_rs2_fpr(issue_instr_o.op));
- assign rs3_fwd_req[k+NR_WB_PORTS] = (mem_q[k].sbe.rd == rs3_i) & ~mem_q[k].pending & mem_q[k].issued & mem_q[k].sbe.valid & (mem_q[k].is_rd_fpr_flag == ariane_pkg::is_imm_fpr(issue_instr_o.op));
+ assign rs1_fwd_req[k+NR_WB_PORTS] = (mem_q[k].sbe.rd == rs1) & ~mem_q[k].pending & mem_q[k].issued & mem_q[k].sbe.valid & (mem_q[k].is_rd_fpr_flag == issue_instr_o.use_rs1_fpr);
+ assign rs2_fwd_req[k+NR_WB_PORTS] = (mem_q[k].sbe.rd == rs2) & ~mem_q[k].pending & mem_q[k].issued & mem_q[k].sbe.valid & (mem_q[k].is_rd_fpr_flag == issue_instr_o.use_rs2_fpr);
+ assign rs3_fwd_req[k+NR_WB_PORTS] = (mem_q[k].sbe.rd == rs3) & ~mem_q[k].pending & mem_q[k].issued & mem_q[k].sbe.valid & (mem_q[k].is_rd_fpr_flag == issue_instr_o.use_imm_fpr);
assign rs_data[k+NR_WB_PORTS] = mem_q[k].sbe.result;
end
@@ -339,8 +342,8 @@ module scoreboard #(
assign rs3_o = (rs3_valid_o) ? rs_data[rs3_fwd_idx] : '0;
// check whether we are accessing GPR[0], rs3 is only used with the FPR!
- assign rs1_valid_o = rs1_valid & ((|rs1_i) | ariane_pkg::is_rs1_fpr(issue_instr_o.op));
- assign rs2_valid_o = rs2_valid & ((|rs2_i) | ariane_pkg::is_rs2_fpr(issue_instr_o.op));
+ assign rs1_valid_o = rs1_valid & ((|rs1) | issue_instr_o.use_rs1_fpr);
+ assign rs2_valid_o = rs2_valid & ((|rs2) | issue_instr_o.use_rs2_fpr);
// sequential process
always_ff @(posedge clk_i or negedge rst_ni) begin : regs
--
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