First commit
This commit is contained in:
commit
736215ffa8
9
.gitattributes
vendored
Normal file
9
.gitattributes
vendored
Normal file
@ -0,0 +1,9 @@
|
||||
# Default behavior, if core.autocrlf is unset.
|
||||
* text=auto
|
||||
|
||||
# Files to be converted to native line endings on checkout.
|
||||
*.cpp text
|
||||
*.h text
|
||||
|
||||
# Text files to always have LF (unix) line endings on checkout.
|
||||
*.zig text eol=lf
|
40
.github/workflows/ci.yml
vendored
Normal file
40
.github/workflows/ci.yml
vendored
Normal file
@ -0,0 +1,40 @@
|
||||
name: CI
|
||||
|
||||
on:
|
||||
pull_request:
|
||||
paths:
|
||||
- ".github/workflows/ci.yml"
|
||||
- "**.zig"
|
||||
push:
|
||||
paths:
|
||||
- ".github/workflows/ci.yml"
|
||||
- "**.zig"
|
||||
branches:
|
||||
- main
|
||||
schedule:
|
||||
- cron: "0 0 * * *"
|
||||
concurrency:
|
||||
# Cancels pending runs when a PR gets updated.
|
||||
group: ${{ github.head_ref || github.run_id }}-${{ github.actor }}
|
||||
cancel-in-progress: true
|
||||
|
||||
jobs:
|
||||
build:
|
||||
strategy:
|
||||
matrix:
|
||||
os: [
|
||||
ubuntu-latest,
|
||||
]
|
||||
runs-on: ${{ matrix.os }}
|
||||
timeout-minutes: 15
|
||||
steps:
|
||||
- name: Checkout
|
||||
uses: actions/checkout@v3
|
||||
- name: Set up Zig
|
||||
uses: goto-bus-stop/setup-zig@v2
|
||||
with:
|
||||
version: master
|
||||
- name: Zig environment variables
|
||||
run: zig env
|
||||
- name: Test
|
||||
run: zig build test
|
2
.gitignore
vendored
Normal file
2
.gitignore
vendored
Normal file
@ -0,0 +1,2 @@
|
||||
zig-cache
|
||||
zig-out
|
70
build.zig
Normal file
70
build.zig
Normal file
@ -0,0 +1,70 @@
|
||||
const std = @import("std");
|
||||
|
||||
// Although this function looks imperative, note that its job is to
|
||||
// declaratively construct a build graph that will be executed by an external
|
||||
// runner.
|
||||
pub fn build(b: *std.Build) void {
|
||||
// Standard target options allows the person running `zig build` to choose
|
||||
// what target to build for. Here we do not override the defaults, which
|
||||
// means any target is allowed, and the default is native. Other options
|
||||
// for restricting supported target set are available.
|
||||
const target = b.standardTargetOptions(.{});
|
||||
|
||||
// Standard optimization options allow the person running `zig build` to select
|
||||
// between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall. Here we do not
|
||||
// set a preferred release mode, allowing the user to decide how to optimize.
|
||||
const optimize = b.standardOptimizeOption(.{});
|
||||
|
||||
const exe = b.addExecutable(.{
|
||||
.name = "compiler",
|
||||
// In this case the main source file is merely a path, however, in more
|
||||
// complicated build scripts, this could be a generated file.
|
||||
.root_source_file = .{ .path = "src/main.zig" },
|
||||
.target = target,
|
||||
.optimize = optimize,
|
||||
});
|
||||
|
||||
// This declares intent for the executable to be installed into the
|
||||
// standard location when the user invokes the "install" step (the default
|
||||
// step when running `zig build`).
|
||||
b.installArtifact(exe);
|
||||
|
||||
// This *creates* a Run step in the build graph, to be executed when another
|
||||
// step is evaluated that depends on it. The next line below will establish
|
||||
// such a dependency.
|
||||
const run_cmd = b.addRunArtifact(exe);
|
||||
|
||||
// By making the run step depend on the install step, it will be run from the
|
||||
// installation directory rather than directly from within the cache directory.
|
||||
// This is not necessary, however, if the application depends on other installed
|
||||
// files, this ensures they will be present and in the expected location.
|
||||
run_cmd.step.dependOn(b.getInstallStep());
|
||||
|
||||
// This allows the user to pass arguments to the application in the build
|
||||
// command itself, like this: `zig build run -- arg1 arg2 etc`
|
||||
if (b.args) |args| {
|
||||
run_cmd.addArgs(args);
|
||||
}
|
||||
|
||||
// This creates a build step. It will be visible in the `zig build --help` menu,
|
||||
// and can be selected like this: `zig build run`
|
||||
// This will evaluate the `run` step rather than the default, which is "install".
|
||||
const run_step = b.step("run", "Run the app");
|
||||
run_step.dependOn(&run_cmd.step);
|
||||
|
||||
// Creates a step for unit testing. This only builds the test executable
|
||||
// but does not run it.
|
||||
const unit_tests = b.addTest(.{
|
||||
.root_source_file = .{ .path = "src/main.zig" },
|
||||
.target = target,
|
||||
.optimize = optimize,
|
||||
});
|
||||
|
||||
const run_unit_tests = b.addRunArtifact(unit_tests);
|
||||
|
||||
// Similar to creating the run step earlier, this exposes a `test` step to
|
||||
// the `zig build --help` menu, providing a way for the user to request
|
||||
// running the unit tests.
|
||||
const test_step = b.step("test", "Run unit tests");
|
||||
test_step.dependOn(&run_unit_tests.step);
|
||||
}
|
124
src/main.zig
Normal file
124
src/main.zig
Normal file
@ -0,0 +1,124 @@
|
||||
const std = @import("std");
|
||||
const page_size = std.mem.page_size;
|
||||
const assert = std.debug.assert;
|
||||
const expectEqual = std.testing.expectEqual;
|
||||
|
||||
const Section = struct {
|
||||
content: []align(page_size) u8,
|
||||
index: usize = 0,
|
||||
};
|
||||
|
||||
const Image = struct {
|
||||
text: Section,
|
||||
rodata: Section,
|
||||
data: Section,
|
||||
entry_point: u32 = 0,
|
||||
|
||||
fn create() !Image {
|
||||
return Image{
|
||||
.text = .{ .content = try mmap(page_size, .{ .executable = true }) },
|
||||
.rodata = .{ .content = try mmap(page_size, .{ .executable = false }) },
|
||||
.data = .{ .content = try mmap(page_size, .{ .executable = false }) },
|
||||
};
|
||||
}
|
||||
|
||||
inline fn mmap(size: usize, flags: packed struct {
|
||||
executable: bool,
|
||||
}) ![]align(page_size) u8 {
|
||||
const protection_flags = std.os.PROT.READ | std.os.PROT.WRITE | if (flags.executable) std.os.PROT.EXEC else 0;
|
||||
const mmap_flags = std.os.MAP.ANONYMOUS | std.os.MAP.PRIVATE;
|
||||
|
||||
return std.os.mmap(null, size, protection_flags, mmap_flags, -1, 0);
|
||||
}
|
||||
|
||||
fn appendCode(image: *Image, code: []const u8) void {
|
||||
const destination = image.text.content[image.text.index..][0..code.len];
|
||||
@memcpy(destination, code);
|
||||
image.text.index += code.len;
|
||||
}
|
||||
|
||||
fn getEntryPoint(image: *const Image, comptime Function: type) *const Function {
|
||||
comptime {
|
||||
assert(@typeInfo(Function) == .Fn);
|
||||
}
|
||||
|
||||
assert(image.text.content.len > 0);
|
||||
return @as(*const Function, @ptrCast(&image.text.content[image.entry_point]));
|
||||
}
|
||||
};
|
||||
|
||||
const Rex = enum(u8) {
|
||||
b = upper_4_bits | (1 << 0),
|
||||
x = upper_4_bits | (1 << 1),
|
||||
r = upper_4_bits | (1 << 2),
|
||||
w = upper_4_bits | (1 << 3),
|
||||
|
||||
const upper_4_bits = 0b100_0000;
|
||||
};
|
||||
|
||||
const prefix_rex_w = [1]u8{@intFromEnum(Rex.w)};
|
||||
const prefix_16_bit_operand = [1]u8{0x66};
|
||||
|
||||
const ret = [1]u8{0xc3};
|
||||
const movabs_to_register_a = [1]u8{0xb8};
|
||||
|
||||
inline fn intToArrayOfBytes(integer: anytype) [@sizeOf(@TypeOf(integer))]u8 {
|
||||
comptime {
|
||||
assert(@typeInfo(@TypeOf(integer)) == .Int);
|
||||
}
|
||||
|
||||
return @as([@sizeOf(@TypeOf(integer))]u8, @bitCast(integer));
|
||||
}
|
||||
|
||||
inline fn movU16ToA(integer: u16) [4]u8 {
|
||||
return prefix_16_bit_operand ++ movabs_to_register_a ++ intToArrayOfBytes(integer);
|
||||
}
|
||||
|
||||
inline fn movU32ToA(integer: u32) [5]u8 {
|
||||
return movabs_to_register_a ++ intToArrayOfBytes(integer);
|
||||
}
|
||||
|
||||
inline fn movU64ToA(integer: u64) [10]u8 {
|
||||
return prefix_rex_w ++ movabs_to_register_a ++ intToArrayOfBytes(integer);
|
||||
}
|
||||
|
||||
test "ret void" {
|
||||
var image = try Image.create();
|
||||
image.appendCode(&ret);
|
||||
|
||||
const function_pointer = image.getEntryPoint(fn () callconv(.C) void);
|
||||
function_pointer();
|
||||
}
|
||||
|
||||
test "ret unsigned integer 16-bit" {
|
||||
var image = try Image.create();
|
||||
const expected_number = 0xffff;
|
||||
image.appendCode(&movU16ToA(expected_number));
|
||||
image.appendCode(&ret);
|
||||
|
||||
const function_pointer = image.getEntryPoint(fn () callconv(.C) u16);
|
||||
const result = function_pointer();
|
||||
try expectEqual(result, expected_number);
|
||||
}
|
||||
|
||||
test "ret unsigned integer 32-bit" {
|
||||
var image = try Image.create();
|
||||
const expected_number = 0xffff_ffff;
|
||||
image.appendCode(&movU32ToA(expected_number));
|
||||
image.appendCode(&ret);
|
||||
|
||||
const function_pointer = image.getEntryPoint(fn () callconv(.C) u32);
|
||||
const result = function_pointer();
|
||||
try expectEqual(result, expected_number);
|
||||
}
|
||||
|
||||
test "ret unsigned integer 64-bit" {
|
||||
var image = try Image.create();
|
||||
const expected_number = 0xffff_ffff_ffff_ffff;
|
||||
image.appendCode(&movU64ToA(expected_number));
|
||||
image.appendCode(&ret);
|
||||
|
||||
const function_pointer = image.getEntryPoint(fn () callconv(.C) u64);
|
||||
const result = function_pointer();
|
||||
try expectEqual(result, expected_number);
|
||||
}
|
Loading…
x
Reference in New Issue
Block a user