setup compiling and running wasm

.gitignore

@@ -1,4 +1,4 @@
-main.exe
+build
 test-dump-asm.o
 test-dump.asm
-test-input.o
+test-input.o

.vscode/c_cpp_properties.json

@@ -5,7 +5,8 @@
             "includePath": [
                 "${workspaceFolder}/**",
                 "C:/MinGW/include/**",
-                "src/**"
+                "src/**",
+                "${workspaceFolder}/emsdk/upstream/lib/clang/17/include/**"
             ],
             "defines": [
                 "_DEBUG",

.vscode/settings.json

@@ -8,5 +8,6 @@
         "errno.h": "c",
         "stdbool.h": "c",
         "sim8086.h": "c"
-    }
+    },
+    "liveServer.settings.root": "./build/web"
 }

Makefile

@@ -1,10 +1,19 @@
-CC=gcc
 CFLAGS=-g -Wall
 
-.DEFAULT_GOAL := main
+.PHONY := cli web clean serve-web
 
-%: src/%.c
+cli: src/cli.c
-	$(CC) -o $@ $< $(CFLAGS)
+	mkdir -p build
+	gcc -o build/cli.exe src/cli.c $(CFLAGS)
+
+web: src/web.c
+	rm -rf build/web
+	mkdir -p build/web
+	emcc -o build/web/sim8086.js src/web.c --no-entry -sEXPORTED_RUNTIME_METHODS=cwrap,AsciiToString -sEXPORTED_FUNCTIONS=_free,_malloc $(CFLAGS)
+	cp -r src/web/* build/web
+
+serve-web:
+	cd build/web && python -m http.server
 
 clean:
-	rm main.exe
+	rm -r build

README.md

@@ -4,6 +4,23 @@ For [Computer, Enhance!](https://www.computerenhance.com/)
 
 Examples gotten from: https://github.com/cmuratori/computer_enhance/tree/main/perfaware/part1
 
+## Building & Running
+
+### CLI
+```shell
+make cli
+./build/cli
+```
+
+### Web
+```shell
+# This assumes that you already have `emcc` in your path somewhere
+make web
+make serve-web
+```
+
+## Manual
+
 8086 reference manual: https://edge.edx.org/c4x/BITSPilani/EEE231/asset/8086_family_Users_Manual_1_.pdf
 Important pages in manual:
 * Registers - 24

src/cli.c

@@ -5,12 +5,7 @@
 #include <errno.h>
 
 #include "os.h"
-#include "sim8086.h"
+#include "sim8086/prelude.h"
-
-#include "sim8086.c"
-#include "sim8086_memory.c"
-#include "sim8086_decoder.c"
-#include "sim8086_simulator.c"
 
 // TODO: refactor cli commands, there is a lot of repeating code for reading assemblies and compiling them.
 
@@ -108,8 +103,7 @@ int dissassemble(FILE *src, FILE *dst) {
         }
 
         instruction_to_str(buff, sizeof(buff), &inst);
-        fprintf(dst, buff);
+        fprintf(dst, "%s\b", buff);
-        fprintf(dst, "\n");
     }
 
     return 0;

src/sim8086/memory.c

@@ -1,8 +1,13 @@
-#include <stdio.h>
-
 // TODO: add error codes
 
-int load_mem_from_stream(struct memory *mem, FILE *stream, u32 start) {
+int load_mem_from_buff(struct memory *mem, u8 *buff, u16 buff_size, u16 start)
+{
+    if (start + buff_size > MEMORY_SIZE) return -1;
+    memcpy(mem->mem + start, buff, buff_size);
+    return 0;
+}
+
+int load_mem_from_stream(struct memory *mem, FILE *stream, u16 start) {
     u32 offset = 0;
     while (true) {
         u8 byte = fgetc(stream);
@@ -14,7 +19,7 @@ int load_mem_from_stream(struct memory *mem, FILE *stream, u32 start) {
     return offset;
 }
 
-int load_mem_from_file(struct memory *mem, const char *filename, u32 start) {
+int load_mem_from_file(struct memory *mem, const char *filename, u16 start) {
     FILE *stream = fopen(filename, "rb");
     if (stream == NULL) {
         return -1;

src/sim8086/prelude.h

@@ -0,0 +1,6 @@
+#include "sim8086.h"
+
+#include "utils.c"
+#include "memory.c"
+#include "decoder.c"
+#include "simulator.c"

src/sim8086/sim8086.h

@@ -1,6 +1,8 @@
 #include <inttypes.h>
 #include <stdbool.h>
 #include <assert.h>
+#include <string.h>
+#include <stdio.h>
 
 #define u32 uint32_t
 #define i32 int32_t
@@ -9,8 +11,20 @@
 #define u8  uint8_t
 #define i8  int8_t
 
+#ifdef SIM8086_EMCC
+#define panic(...) \
+    emscripten_log(EM_LOG_ERROR, "PANIC(%s:%d): ", __FILE__, __LINE__); \
+    emscripten_log(EM_LOG_ERROR, __VA_ARGS__); \
+    abort()
+#define todo(...) \
+    emscripten_log(EM_LOG_WARN, "TODO(%s:%d): ", __FILE__, __LINE__); \
+    emscripten_log(EM_LOG_WARN, __VA_ARGS__); \
+    abort()
+#else
 #define panic(...) fprintf(stderr, "PANIC(%s:%d): ", __FILE__, __LINE__); fprintf(stderr, __VA_ARGS__); abort()
 #define todo(...) fprintf(stderr, "TODO(%s:%d): ", __FILE__, __LINE__); fprintf(stderr, __VA_ARGS__); abort()
+#endif
+
 #define ARRAY_LEN(arr) (sizeof(arr) / sizeof(arr[0]))
 #define MEMORY_SIZE 65536 // 2^16
 

src/web.c

@@ -0,0 +1,66 @@
+#include <emscripten.h>
+
+#define SIM8086_EMCC
+#include "sim8086/prelude.h"
+
+#define EXPORT EMSCRIPTEN_KEEPALIVE
+#define dbg(...) emscripten_log(EM_LOG_CONSOLE, __VA_ARGS__)
+
+EXPORT struct memory memory_state;
+EXPORT struct cpu_state cpu_state;
+EXPORT struct instruction current_instruction;
+
+/* -------------------- Decoder ----------------------- */
+
+EXPORT int decode_inst_at_ip() {
+    return decode_instruction(&memory_state, &cpu_state.ip, &current_instruction);
+}
+
+EXPORT void get_inst_str(char *buff, size_t buff_size) {
+    instruction_to_str(buff, buff_size, &current_instruction);
+}
+
+/* -------------------- Memory ----------------------- */
+
+EXPORT int load_to_memory_state(u8 *assembly, u16 assembly_size, u16 start) {
+    return load_mem_from_buff(&memory_state, assembly, assembly_size, start);
+}
+
+EXPORT u8 *get_memory_state_base() {
+    return memory_state.mem;
+}
+
+EXPORT size_t get_memory_state_size(u8 *assembly, u16 assembly_size, u16 start) {
+    return MEMORY_SIZE;
+}
+
+/* -------------------- CPU ----------------------- */
+
+EXPORT void cpu_reset()
+{
+    memset(&cpu_state, 0, sizeof(cpu_state));
+}
+
+#define CPU_STATE_GETTER(field) EXPORT u16 cpu_get_##field() { return cpu_state.field; }
+#define CPU_STATE_SETTER(field) EXPORT void cpu_set_##field(u16 value) { cpu_state.field = value; }
+#define CPU_STATE_ACCESOR(field) CPU_STATE_SETTER(field) CPU_STATE_GETTER(field)
+
+CPU_STATE_ACCESOR(ip)
+CPU_STATE_ACCESOR(ax)
+CPU_STATE_ACCESOR(bx)
+CPU_STATE_ACCESOR(cx)
+CPU_STATE_ACCESOR(dx)
+CPU_STATE_ACCESOR(sp)
+CPU_STATE_ACCESOR(bp)
+CPU_STATE_ACCESOR(si)
+CPU_STATE_ACCESOR(di)
+
+EXPORT bool cpu_get_zero_flag()
+{
+    return cpu_state.flags.zero;
+}
+
+EXPORT bool cpu_get_sign_flag()
+{
+    return cpu_state.flags.sign;
+}

src/web/index.html

@@ -0,0 +1,225 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>sim8086.wasm</title>
+    <script src="https://cdn.tailwindcss.com"></script>
+    <link rel="preconnect" href="https://fonts.googleapis.com">
+    <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
+    <link href="https://fonts.googleapis.com/css2?family=Source+Sans+Pro:wght@600&display=swap" rel="stylesheet">
+    <script>
+        tailwind.config = {
+            theme: {
+                fontFamily: {
+                    serif: ["Source Sans Pro", "sans-serif"]
+                }
+            }
+        }
+    </script>
+    <style>
+        .register {
+            display: inline-block;
+
+            background: #AAA;
+            display: flex;
+            gap: 0.25rem;
+        }
+        .register__name, .register__value {
+            display: inline-block;
+            background: #BBB;
+        }
+        .register__value {
+            text-align: center;
+            padding: 0.25ch 1ch;
+            flex-grow: 1;
+        }
+        .register__value--byte {
+            width: 8ch;
+        }
+        .register__name {
+            text-align: right;
+            min-width: 4ch
+        }
+    </style>
+</head>
+<body class="h-screen font-serif">
+<main class="bg-red-500 max-w-screen-md m-auto h-full p-5 gap-3 flex flex-col">
+    <h1 class="font-bold text-4xl m-auto text-center grow-0">sim8086.wasm</h1>
+    <div class="flex flex-col min-h-max grow gap-4">
+        <div class="bg-green-500">a</div>
+        <div class="bg-blue-500 grow flex flex-row gap-4">
+            <div class="bg-green-500 grow">
+
+            </div>
+            <div class="bg-green-500 grow flex flex-row basis-1/4">
+                <div class="bg-cyan-500 flex flex-col gap-1">
+                    <register-field reg="ax" has-low-high></register-field>
+                    <register-field reg="bx" has-low-high></register-field>
+                    <register-field reg="cx" has-low-high></register-field>
+                    <register-field reg="dx" has-low-high></register-field>
+                    <register-field reg="sp"></register-field>
+                    <register-field reg="bp"></register-field>
+                    <register-field reg="si"></register-field>
+                    <register-field reg="di"></register-field>
+                    <register-field reg="ip" readonly></register-field>
+                    <register-input reg="ax" position="low"> </register-input>
+                </div>
+                <div class="bg-cyan-500">
+                </div>
+            </div>
+        </div>
+        <div class="bg-green-500 grow basis-1/4"></div>
+    </div>
+</main>
+
+<script src="sim8086.js"></script>
+<script>
+    const registers = {}
+    for (const reg of ["ax", "bx", "cx", "dx", "sp", "bp", "si", "di", "ip"]) {
+        registers[reg] = {
+            set: Module.cwrap(`cpu_set_${reg}`, null, ["number"]),
+            get: Module.cwrap(`cpu_get_${reg}`, "number", [])
+        }
+    }
+
+    class RegisterInputElement extends HTMLInputElement {
+        /** @type {"low"|"high"|"full"} */
+        position = "full"
+        reg = "<unknown>"
+        /** @type {"hex"|"decimal"|"binary"} */
+        format = "decimal"
+        validFormatSymbols = {
+            hex: "0123456789abcdef",
+            decimal: "0123456789",
+            binary: "01"
+        }
+
+        onChange(e) {
+            let parsed = parseInt(this.value, this.validFormatSymbols[this.format].length)
+            if (parsed == NaN) {
+                registers[this.reg].set(0)
+            } else {
+                registers[this.reg].set(parsed)
+            }
+            this.render()
+        }
+
+        onKeyPress(e) {
+            if (!this.validFormatSymbols[this.format].includes(e.key.toLocaleLowerCase())) {
+                e.preventDefault()
+            }
+        }
+
+        connectedCallback() {
+            this.reg = this.getAttribute("reg").toLocaleLowerCase()
+            this.position = this.getAttribute("position")
+            this.classList.add("register__value")
+            if (this.position !== "full") {
+                this.classList.add("register__value--byte")
+            }
+            this.addEventListener("change", this.onChange)
+            this.addEventListener("keypress", this.onKeyPress)
+        }
+        getRegValue() {
+            const value = registers[this.reg].get()
+            switch (this.position) {
+                case "full": return value & 0xFFFF
+                case "low":  return value & 0xFF
+                case "high": return (value >> 8) & 0xFF
+            }
+        }
+
+        render() {
+            const value = this.getRegValue()
+            if (this.format == "hex") {
+                this.value = value.toString(16).padStart(this.position == "full" ? 4 : 2, "0")
+            } else if (this.format == "decimal") {
+                this.value = value
+            } else if (this.format == "binary") {
+                this.value = value.toString(2).padStart(this.position == "full" ? 16 : 8, "0")
+            }
+        }
+    }
+    customElements.define("register-input", RegisterInputElement, { extends: "input" })
+
+    class RegisterElement extends HTMLElement {
+        reg = "<unknown>"
+        readonly = false
+        hasHighLow = false
+
+        /** @type {RegisterInputElement} */
+        valueElement = undefined
+        /** @type {RegisterInputElement} */
+        highByteElement = undefined
+        /** @type {RegisterInputElement} */
+        lowByteElement = undefined
+
+        constructor() {
+            super()
+            this.readonly = this.getAttribute("readonly") !== null
+            this.reg = this.getAttribute("reg").toLocaleLowerCase()
+            this.hasHighLow = this.getAttribute("has-low-high") !== null
+            this.classList.add("register")
+
+            const nameElement = this.appendChild(document.createElement("span"))
+            nameElement.classList.add("register__name")
+            nameElement.innerText = this.reg.toUpperCase()
+
+            if (this.hasHighLow) {
+                const highByteElem = document.createElement("input", { is: "register-input" })
+                highByteElem.setAttribute("reg", this.reg)
+                highByteElem.setAttribute("position", "high")
+                if (this.readonly) highByteElem.setAttribute("readonly", "")
+                this.highByteElement = this.appendChild(highByteElem)
+
+                const lowByteElem = document.createElement("input", { is: "register-input" })
+                lowByteElem.setAttribute("reg", this.reg)
+                lowByteElem.setAttribute("position", "low")
+                if (this.readonly) lowByteElem.setAttribute("readonly", "")
+                this.lowByteElement = this.appendChild(lowByteElem)
+            } else {
+                const elem = document.createElement("input", { is: "register-input" })
+                elem.setAttribute("reg", this.reg)
+                elem.setAttribute("position", "full")
+                if (this.readonly) elem.setAttribute("readonly", "")
+                this.valueElement = this.appendChild(elem)
+            }
+        }
+
+        render() {
+            if (this.hasHighLow) {
+                this.lowByteElement.render()
+                this.highByteElement.render()
+            } else {
+                this.valueElement.render()
+            }
+        }
+    }
+    customElements.define("register-field", RegisterElement)
+
+    const assembly = [137, 217]
+    const decodeInstructionAtIP = Module.cwrap("decode_inst_at_ip", "number", [])
+    const loadAsmToMemory = Module.cwrap("load_to_memory_state", null, ["array", "number", "number"])
+    const getInstructionString = Module.cwrap("get_inst_str", null, ["number", "number"])
+
+    Module.onRuntimeInitialized = () => {
+        loadAsmToMemory(assembly, assembly.length, 0)
+        console.log(decodeInstructionAtIP())
+        console.log(getCurrentInstruction())
+
+        for (const elem of document.getElementsByTagName("register-field")) {
+            elem.render()
+        }
+    }
+
+    function getCurrentInstruction() {
+        const inst = Module._malloc(64)
+        getInstructionString(inst, 64)
+        const text = Module.AsciiToString(inst)
+        Module._free(inst)
+        return text
+    }
+</script>
+</body>
+</html>