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Removed multiplier for lab 2

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David Harris 2021-02-17 16:06:16 -05:00
parent e8d3c7d9e7
commit 492ec0ee78
3 changed files with 0 additions and 114 deletions
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4
wally-pipelined/src/ieu/controller.sv
View File

@ -94,14 +94,10 @@ module controller(
7'b0100011: ControlsD = 21'b0_001_01_01_000_0_00_0_0_0_0_0_0_0; // sw
7'b0110011: if (Funct7D == 7'b0000000 || Funct7D == 7'b0100000)
ControlsD = 21'b1_000_00_00_000_0_10_0_0_0_0_0_0_0; // R-type
else if (Funct7D == 7'b0000001 && `M_SUPPORTED)
ControlsD = 21'b1_000_00_00_100_0_00_0_0_0_0_0_1_0; // Multiply/Divide
else
ControlsD = 21'b0_000_00_00_000_0_00_0_0_0_0_0_0_1; // non-implemented instruction
7'b0111011: if ((Funct7D == 7'b0000000 || Funct7D == 7'b0100000) && `XLEN == 64)
ControlsD = 21'b1_000_00_00_000_0_10_0_0_1_0_0_0_0; // R-type W instructions for RV64i
else if (Funct7D == 7'b0000001 && `M_SUPPORTED && `XLEN == 64)
ControlsD = 21'b1_000_00_00_100_0_00_0_0_1_0_0_1_0; // W-type Multiply/Divide
else
ControlsD = 21'b0_000_00_00_000_0_00_0_0_0_0_0_0_1; // non-implemented instruction
7'b1100011: ControlsD = 21'b0_010_00_00_000_1_01_0_0_0_0_0_0_0; // beq

77
wally-pipelined/src/muldiv/mul.sv
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@ -1,77 +0,0 @@
///////////////////////////////////////////
// mul.sv
//
// Written: David_Harris@hmc.edu 9 January 2021
// Modified:
//
// Purpose: Multiply instructions
//
// A component of the Wally configurable RISC-V project.
//
// Copyright (C) 2021 Harvey Mudd College & Oklahoma State University
//
// Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation
// files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy,
// modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software
// is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
// BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
// OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
///////////////////////////////////////////
`include "wally-config.vh"
module mul (
// Execute Stage interface
input logic [`XLEN-1:0] SrcAE, SrcBE,
input logic [2:0] Funct3E,
output logic [`XLEN*2-1:0] ProdE
);
// Number systems
// Let A' = sum(i=0, XLEN-2, A[i]*2^i)
// Unsigned: A = A' + A[XLEN-1]*2^(XLEN-1)
// Signed: A = A' - A[XLEN-1]*2^(XLEN-1)
// Multiplication: A*B
// Let P' = A' * B'
// PA = (A' * B[XLEN-1])
// PB = (B' * A[XLEN-1])
// PP = A[XLEN-1] * B[XLEN-1]
// Signed * Signed = P' + (-PA - PB)*2^(XLEN-1) + PP*2^(2XLEN-2)
// Signed * Unsigned = P' + ( PA - PB)*2^(XLEN-1) - PP*2^(2XLEN-2)
// Unsigned * Unsigned = P' + ( PA + PB)*2^(XLEN-1) + PP*2^(2XLEN-2)
logic [`XLEN*2-1:0] PP1, PP2, PP3, PP4;
logic [`XLEN*2-1:0] Pprime;
logic [`XLEN-2:0] PA, PB;
logic PP;
logic MULH, MULHSU, MULHU;
// portions of product
assign Pprime = {1'b0, SrcAE[`XLEN-2:0]} * {1'b0, SrcBE[`XLEN-2:0]};
assign PA = {(`XLEN-1){SrcAE[`XLEN-1]}} & SrcBE[`XLEN-2:0];
assign PB = {(`XLEN-1){SrcBE[`XLEN-1]}} & SrcAE[`XLEN-2:0];
assign PP = SrcAE[`XLEN-1] & SrcBE[`XLEN-1];
// flavor of multiplication
assign MULH = (Funct3E == 2'b01);
assign MULHSU = (Funct3E == 2'b10);
assign MULHU = (Funct3E == 2'b11);
// Handle signs
assign PP1 = Pprime; // same for all flavors
assign PP2 = {2'b00, (MULH | MULHSU) ? ~PA : PA, {(`XLEN-1){1'b0}}};
assign PP3 = {2'b00, (MULH) ? ~PB : PB, {(`XLEN-1){1'b0}}};
always_comb
if (MULH) PP4 = {1'b1, PP, {(`XLEN-3){1'b0}}, 1'b1, {(`XLEN){1'b0}}};
else if (MULHSU) PP4 = {1'b1, ~PP, {(`XLEN-2){1'b0}}, 1'b1, {(`XLEN-1){1'b0}}};
else PP4 = {1'b0, PP, {(`XLEN*2-2){1'b0}}};
assign ProdE = PP1 + PP2 + PP3 + PP4; //SrcAE * SrcBE;
endmodule

33
wally-pipelined/src/muldiv/muldiv.sv
View File

@ -46,39 +46,6 @@ module muldiv (
logic [`XLEN-1:0] QuotE, RemE;
logic [`XLEN*2-1:0] ProdE;
mul mul(.*);
/*
if (`XLEN==32) begin
int32div div(.clk(clk), .reset(reset),
.N(SrcAE), .D(SrcBE), .Q(QuotE), .rem0(RemE),
.start(), .div0(), .done(), .divdone());
end else begin // XLEN=64
int64div div(.clk(clk), .reset(reset),
.N(SrcAE), .D(SrcBE), .Q(QuotE), .rem0(RemE),
.start(), .div0(), .done(), .divdone());
end
*/
// Select result
always_comb
case (Funct3E)
3'b000: PrelimResultE = ProdE[`XLEN-1:0];
3'b001: PrelimResultE = ProdE[`XLEN*2-1:`XLEN];
3'b010: PrelimResultE = ProdE[`XLEN*2-1:`XLEN];
3'b011: PrelimResultE = ProdE[`XLEN*2-1:`XLEN];
3'b100: PrelimResultE = QuotE;
3'b101: PrelimResultE = QuotE;
3'b110: PrelimResultE = RemE;
3'b111: PrelimResultE = RemE;
endcase
// Handle sign extension for W-type instructions
if (`XLEN == 64) begin // RV64 has W-type instructions
assign MulDivResultE = W64E ? {{32{PrelimResultE[31]}}, PrelimResultE[31:0]} : PrelimResultE;
end else begin // RV32 has no W-type instructions
assign MulDivResultE = PrelimResultE;
end
floprc #(`XLEN) MulDivResultMReg(clk, reset, FlushM, MulDivResultE, MulDivResultM);
floprc #(`XLEN) MulDivResultWReg(clk, reset, FlushW, MulDivResultM, MulDivResultW);