diff options
Diffstat (limited to 'src-self-hosted/codegen')
| -rw-r--r-- | src-self-hosted/codegen/c.zig | 151 |
1 files changed, 99 insertions, 52 deletions
diff --git a/src-self-hosted/codegen/c.zig b/src-self-hosted/codegen/c.zig index 907bbccda1..76585a6dfb 100644 --- a/src-self-hosted/codegen/c.zig +++ b/src-self-hosted/codegen/c.zig @@ -94,6 +94,28 @@ fn genArray(file: *C, decl: *Decl) !void { return file.fail(decl.src(), "TODO non-byte arrays", .{}); } +const Context = struct { + file: *C, + decl: *Decl, + inst_map: std.AutoHashMap(*Inst, []u8), + argdex: usize = 0, + unnamed_index: usize = 0, + + fn name(self: *Context) ![]u8 { + const val = try std.fmt.allocPrint(self.file.base.allocator, "__temp_{}", .{self.unnamed_index}); + self.unnamed_index += 1; + return val; + } + + fn deinit(self: *Context) void { + for (self.inst_map.items()) |kv| { + self.file.base.allocator.free(kv.value); + } + self.inst_map.deinit(); + self.* = undefined; + } +}; + fn genFn(file: *C, decl: *Decl) !void { const writer = file.main.writer(); const tv = decl.typed_value.most_recent.typed_value; @@ -102,24 +124,31 @@ fn genFn(file: *C, decl: *Decl) !void { try writer.writeAll(" {"); + var ctx = Context{ + .file = file, + .decl = decl, + .inst_map = std.AutoHashMap(*Inst, []u8).init(file.base.allocator), + }; + defer ctx.deinit(); + const func: *Module.Fn = tv.val.cast(Value.Payload.Function).?.func; const instructions = func.analysis.success.instructions; - var argdex: usize = 0; if (instructions.len > 0) { try writer.writeAll("\n"); for (instructions) |inst| { - switch (inst.tag) { - .assembly => try genAsm(file, inst.castTag(.assembly).?, decl, &argdex), - .call => try genCall(file, inst.castTag(.call).?, decl), - .ret => try genRet(file, inst.castTag(.ret).?, decl, tv.ty.fnReturnType()), - .retvoid => try file.main.writer().print(" return;\n", .{}), - .arg => {}, - .dbg_stmt => try genDbgStmt(file, inst.castTag(.dbg_stmt).?, decl), - .breakpoint => try genBreak(file, inst.castTag(.breakpoint).?, decl), - .unreach => try genUnreach(file, inst.castTag(.unreach).?, decl), - // This will be handled correctly later? - .intcast => {}, + if (switch (inst.tag) { + .assembly => try genAsm(&ctx, inst.castTag(.assembly).?), + .call => try genCall(&ctx, inst.castTag(.call).?), + .ret => try genRet(&ctx, inst.castTag(.ret).?), + .retvoid => try genRetVoid(&ctx), + .arg => try genArg(&ctx), + .dbg_stmt => try genDbgStmt(&ctx, inst.castTag(.dbg_stmt).?), + .breakpoint => try genBreak(&ctx, inst.castTag(.breakpoint).?), + .unreach => try genUnreach(&ctx, inst.castTag(.unreach).?), + .intcast => try genIntCast(&ctx, inst.castTag(.intcast).?), else => |e| return file.fail(decl.src(), "TODO implement C codegen for {}", .{e}), + }) |name| { + try ctx.inst_map.putNoClobber(inst, name); } } } @@ -127,27 +156,40 @@ fn genFn(file: *C, decl: *Decl) !void { try writer.writeAll("}\n\n"); } -fn genRet(file: *C, inst: *Inst.UnOp, decl: *Decl, expected_return_type: Type) !void { - return file.fail(decl.src(), "TODO return {}", .{expected_return_type}); +fn genArg(ctx: *Context) !?[]u8 { + const name = try std.fmt.allocPrint(ctx.file.base.allocator, "arg{}", .{ctx.argdex}); + ctx.argdex += 1; + return name; +} + +fn genRetVoid(ctx: *Context) !?[]u8 { + try ctx.file.main.writer().print(" return;\n", .{}); + return null; } -fn genIntCast(file: *C, inst: *Inst.UnOp, decl: *Decl, argdex: *usize) !void { +fn genRet(ctx: *Context, inst: *Inst.UnOp) !?[]u8 { + return ctx.file.fail(ctx.decl.src(), "TODO return", .{}); +} + +fn genIntCast(ctx: *Context, inst: *Inst.UnOp) !?[]u8 { + if (inst.base.isUnused()) + return null; const op = inst.operand; - const writer = file.main.writer(); - try writer.writeByte('('); - try renderType(file, writer, inst.base.ty, decl.src()); - try writer.writeByte(')'); - if (op.castTag(.arg)) |_| { - try writer.print("arg{}", .{argdex.*}); - argdex.* += 1; - } else { - return file.fail(decl.src(), "TODO intcast {} to {}", .{ op, inst.base.ty }); - } + const writer = ctx.file.main.writer(); + const name = try ctx.name(); + const from = ctx.inst_map.get(op) orelse + return ctx.file.fail(ctx.decl.src(), "Internal error in C backend: intCast argument not found in inst_map", .{}); + try writer.writeAll(" const "); + try renderType(ctx.file, writer, inst.base.ty, ctx.decl.src()); + try writer.print(" {} = (", .{name}); + try renderType(ctx.file, writer, inst.base.ty, ctx.decl.src()); + try writer.print("){};\n", .{from}); + return name; } -fn genCall(file: *C, inst: *Inst.Call, decl: *Decl) !void { - const writer = file.main.writer(); - const header = file.header.writer(); +fn genCall(ctx: *Context, inst: *Inst.Call) !?[]u8 { + const writer = ctx.file.main.writer(); + const header = ctx.file.header.writer(); try writer.writeAll(" "); if (inst.func.castTag(.constant)) |func_inst| { if (func_inst.val.cast(Value.Payload.Function)) |func_val| { @@ -158,9 +200,9 @@ fn genCall(file: *C, inst: *Inst.Call, decl: *Decl) !void { try writer.print("(void)", .{}); } const tname = mem.spanZ(target.name); - if (file.called.get(tname) == null) { - try file.called.put(tname, void{}); - try renderFunctionSignature(file, header, target); + if (ctx.file.called.get(tname) == null) { + try ctx.file.called.put(tname, void{}); + try renderFunctionSignature(ctx.file, header, target); try header.writeAll(";\n"); } try writer.print("{}(", .{tname}); @@ -170,61 +212,65 @@ fn genCall(file: *C, inst: *Inst.Call, decl: *Decl) !void { try writer.writeAll(", "); } if (arg.cast(Inst.Constant)) |con| { - try renderValue(file, writer, con.val, decl.src()); + try renderValue(ctx.file, writer, con.val, ctx.decl.src()); } else { - return file.fail(decl.src(), "TODO call pass arg {}", .{arg}); + return ctx.file.fail(ctx.decl.src(), "TODO call pass arg {}", .{arg}); } } } try writer.writeAll(");\n"); } else { - return file.fail(decl.src(), "TODO non-function call target?", .{}); + return ctx.file.fail(ctx.decl.src(), "TODO non-function call target?", .{}); } } else { - return file.fail(decl.src(), "TODO non-constant call inst?", .{}); + return ctx.file.fail(ctx.decl.src(), "TODO non-constant call inst?", .{}); } + return null; } -fn genDbgStmt(file: *C, inst: *Inst.NoOp, decl: *Decl) !void { +fn genDbgStmt(ctx: *Context, inst: *Inst.NoOp) !?[]u8 { // TODO emit #line directive here with line number and filename + return null; } -fn genBreak(file: *C, inst: *Inst.NoOp, decl: *Decl) !void { +fn genBreak(ctx: *Context, inst: *Inst.NoOp) !?[]u8 { // TODO ?? + return null; } -fn genUnreach(file: *C, inst: *Inst.NoOp, decl: *Decl) !void { - try file.main.writer().writeAll(" zig_unreachable();\n"); +fn genUnreach(ctx: *Context, inst: *Inst.NoOp) !?[]u8 { + try ctx.file.main.writer().writeAll(" zig_unreachable();\n"); + return null; } -fn genAsm(file: *C, as: *Inst.Assembly, decl: *Decl, argdex: *usize) !void { - const writer = file.main.writer(); +fn genAsm(ctx: *Context, as: *Inst.Assembly) !?[]u8 { + const writer = ctx.file.main.writer(); try writer.writeAll(" "); for (as.inputs) |i, index| { if (i[0] == '{' and i[i.len - 1] == '}') { const reg = i[1 .. i.len - 1]; const arg = as.args[index]; try writer.writeAll("register "); - try renderType(file, writer, arg.ty, decl.src()); + try renderType(ctx.file, writer, arg.ty, ctx.decl.src()); try writer.print(" {}_constant __asm__(\"{}\") = ", .{ reg, reg }); + // TODO merge constant handling into inst_map as well if (arg.castTag(.constant)) |c| { - try renderValue(file, writer, c.val, decl.src()); - } else if (arg.castTag(.arg)) |inst| { - try writer.print("arg{}", .{argdex.*}); - argdex.* += 1; - } else if (arg.castTag(.intcast)) |inst| { - try genIntCast(file, inst, decl, argdex); + try renderValue(ctx.file, writer, c.val, ctx.decl.src()); + try writer.writeAll(";\n "); } else { - return file.fail(decl.src(), "TODO non-constant inline asm args ({})", .{arg.tag}); + const gop = try ctx.inst_map.getOrPut(arg); + if (!gop.found_existing) { + return ctx.file.fail(ctx.decl.src(), "Internal error in C backend: asm argument not found in inst_map", .{}); + } + try writer.print("{};\n ", .{gop.entry.value}); } - try writer.writeAll(";\n "); } else { - return file.fail(decl.src(), "TODO non-explicit inline asm regs", .{}); + return ctx.file.fail(ctx.decl.src(), "TODO non-explicit inline asm regs", .{}); } } try writer.print("__asm {} (\"{}\"", .{ if (as.is_volatile) @as([]const u8, "volatile") else "", as.asm_source }); if (as.output) |o| { - return file.fail(decl.src(), "TODO inline asm output", .{}); + return ctx.file.fail(ctx.decl.src(), "TODO inline asm output", .{}); } if (as.inputs.len > 0) { if (as.output == null) { @@ -246,4 +292,5 @@ fn genAsm(file: *C, as: *Inst.Assembly, decl: *Decl, argdex: *usize) !void { } } try writer.writeAll(");\n"); + return null; } |