Implement Instruction Pipeline #3

Merged
paoda merged 20 commits from pipeline into main 2022-10-17 19:42:42 +00:00
5 changed files with 29 additions and 29 deletions
Showing only changes of commit f5bd20bc2a - Show all commits

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@ -2,8 +2,8 @@ const Bus = @import("../../Bus.zig");
const Arm7tdmi = @import("../../cpu.zig").Arm7tdmi;
const InstrFn = @import("../../cpu.zig").arm.InstrFn;
const rotateRight = @import("../barrel_shifter.zig").rotateRight;
const execute = @import("../barrel_shifter.zig").execute;
const exec = @import("../barrel_shifter.zig").exec;
const ror = @import("../barrel_shifter.zig").ror;
pub fn dataProcessing(comptime I: bool, comptime S: bool, comptime kind: u4) InstrFn {
return struct {
@ -18,7 +18,7 @@ pub fn dataProcessing(comptime I: bool, comptime S: bool, comptime kind: u4) Ins
const op1 = cpu.r[rn];
const amount = @truncate(u8, (opcode >> 8 & 0xF) << 1);
const op2 = if (I) rotateRight(S, &cpu.cpsr, opcode & 0xFF, amount) else execute(S, cpu, opcode);
const op2 = if (I) ror(S, &cpu.cpsr, opcode & 0xFF, amount) else exec(S, cpu, opcode);
// Undo special condition from above
if (!I and opcode >> 4 & 1 == 1) cpu.r[15] -= 4;
@ -146,7 +146,7 @@ pub fn dataProcessing(comptime I: bool, comptime S: bool, comptime kind: u4) Ins
} else {
// TST, TEQ specific
// Barrel Shifter should always calc CPSR C in TST
if (!S) _ = execute(true, cpu, opcode);
if (!S) _ = exec(true, cpu, opcode);
}
},
}

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@ -17,7 +17,7 @@ pub fn singleDataTransfer(comptime I: bool, comptime P: bool, comptime U: bool,
// rn is r15 and L is not set, the PC is 12 ahead
const base = cpu.r[rn] + if (!L and rn == 0xF) 4 else @as(u32, 0);
const offset = if (I) shifter.immShift(false, cpu, opcode) else opcode & 0xFFF;
const offset = if (I) shifter.immediate(false, cpu, opcode) else opcode & 0xFFF;
const modified_base = if (U) base +% offset else base -% offset;
var address = if (P) modified_base else base;

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@ -5,31 +5,31 @@ const CPSR = @import("../cpu.zig").PSR;
const rotr = @import("../../util.zig").rotr;
pub fn execute(comptime S: bool, cpu: *Arm7tdmi, opcode: u32) u32 {
pub fn exec(comptime S: bool, cpu: *Arm7tdmi, opcode: u32) u32 {
var result: u32 = undefined;
if (opcode >> 4 & 1 == 1) {
result = registerShift(S, cpu, opcode);
result = register(S, cpu, opcode);
} else {
result = immShift(S, cpu, opcode);
result = immediate(S, cpu, opcode);
}
return result;
}
fn registerShift(comptime S: bool, cpu: *Arm7tdmi, opcode: u32) u32 {
fn register(comptime S: bool, cpu: *Arm7tdmi, opcode: u32) u32 {
const rs_idx = opcode >> 8 & 0xF;
const rm = cpu.r[opcode & 0xF];
const rs = @truncate(u8, cpu.r[rs_idx]);
return switch (@truncate(u2, opcode >> 5)) {
0b00 => logicalLeft(S, &cpu.cpsr, rm, rs),
0b01 => logicalRight(S, &cpu.cpsr, rm, rs),
0b10 => arithmeticRight(S, &cpu.cpsr, rm, rs),
0b11 => rotateRight(S, &cpu.cpsr, rm, rs),
0b00 => lsl(S, &cpu.cpsr, rm, rs),
0b01 => lsr(S, &cpu.cpsr, rm, rs),
0b10 => asr(S, &cpu.cpsr, rm, rs),
0b11 => ror(S, &cpu.cpsr, rm, rs),
};
}
pub fn immShift(comptime S: bool, cpu: *Arm7tdmi, opcode: u32) u32 {
pub fn immediate(comptime S: bool, cpu: *Arm7tdmi, opcode: u32) u32 {
const amount = @truncate(u8, opcode >> 7 & 0x1F);
const rm = cpu.r[opcode & 0xF];
@ -60,17 +60,17 @@ pub fn immShift(comptime S: bool, cpu: *Arm7tdmi, opcode: u32) u32 {
}
} else {
switch (@truncate(u2, opcode >> 5)) {
0b00 => result = logicalLeft(S, &cpu.cpsr, rm, amount),
0b01 => result = logicalRight(S, &cpu.cpsr, rm, amount),
0b10 => result = arithmeticRight(S, &cpu.cpsr, rm, amount),
0b11 => result = rotateRight(S, &cpu.cpsr, rm, amount),
0b00 => result = lsl(S, &cpu.cpsr, rm, amount),
0b01 => result = lsr(S, &cpu.cpsr, rm, amount),
0b10 => result = asr(S, &cpu.cpsr, rm, amount),
0b11 => result = ror(S, &cpu.cpsr, rm, amount),
}
}
return result;
}
pub fn logicalLeft(comptime S: bool, cpsr: *CPSR, rm: u32, total_amount: u8) u32 {
pub fn lsl(comptime S: bool, cpsr: *CPSR, rm: u32, total_amount: u8) u32 {
const amount = @truncate(u5, total_amount);
const bit_count: u8 = @typeInfo(u32).Int.bits;
@ -97,7 +97,7 @@ pub fn logicalLeft(comptime S: bool, cpsr: *CPSR, rm: u32, total_amount: u8) u32
return result;
}
pub fn logicalRight(comptime S: bool, cpsr: *CPSR, rm: u32, total_amount: u32) u32 {
pub fn lsr(comptime S: bool, cpsr: *CPSR, rm: u32, total_amount: u32) u32 {
const amount = @truncate(u5, total_amount);
const bit_count: u8 = @typeInfo(u32).Int.bits;
@ -121,7 +121,7 @@ pub fn logicalRight(comptime S: bool, cpsr: *CPSR, rm: u32, total_amount: u32) u
return result;
}
pub fn arithmeticRight(comptime S: bool, cpsr: *CPSR, rm: u32, total_amount: u8) u32 {
pub fn asr(comptime S: bool, cpsr: *CPSR, rm: u32, total_amount: u8) u32 {
const amount = @truncate(u5, total_amount);
const bit_count: u8 = @typeInfo(u32).Int.bits;
@ -138,7 +138,7 @@ pub fn arithmeticRight(comptime S: bool, cpsr: *CPSR, rm: u32, total_amount: u8)
return result;
}
pub fn rotateRight(comptime S: bool, cpsr: *CPSR, rm: u32, total_amount: u8) u32 {
pub fn ror(comptime S: bool, cpsr: *CPSR, rm: u32, total_amount: u8) u32 {
const result = rotr(u32, rm, total_amount);
if (S and total_amount != 0) {

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@ -5,10 +5,10 @@ const InstrFn = @import("../../cpu.zig").thumb.InstrFn;
const adc = @import("../arm/data_processing.zig").adc;
const sbc = @import("../arm/data_processing.zig").sbc;
const lsl = @import("../barrel_shifter.zig").logicalLeft;
const lsr = @import("../barrel_shifter.zig").logicalRight;
const asr = @import("../barrel_shifter.zig").arithmeticRight;
const ror = @import("../barrel_shifter.zig").rotateRight;
const lsl = @import("../barrel_shifter.zig").lsl;
const lsr = @import("../barrel_shifter.zig").lsr;
const asr = @import("../barrel_shifter.zig").asr;
const ror = @import("../barrel_shifter.zig").ror;
pub fn fmt4(comptime op: u4) InstrFn {
return struct {

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@ -6,9 +6,9 @@ const InstrFn = @import("../../cpu.zig").thumb.InstrFn;
const add = @import("../arm/data_processing.zig").add;
const lsl = @import("../barrel_shifter.zig").logicalLeft;
const lsr = @import("../barrel_shifter.zig").logicalRight;
const asr = @import("../barrel_shifter.zig").arithmeticRight;
const lsl = @import("../barrel_shifter.zig").lsl;
const lsr = @import("../barrel_shifter.zig").lsr;
const asr = @import("../barrel_shifter.zig").asr;
pub fn fmt1(comptime op: u2, comptime offset: u5) InstrFn {
return struct {