Commit 8d6cadee16

Noam Preil <pleasantatk@gmail.com>
2020-07-13 07:47:44
CBE: Code cleanup
1 parent 4a46248
Changed files (1)
src-self-hosted
src-self-hosted/cgen.zig
@@ -1,9 +1,11 @@
 const link = @import("link.zig");
 const Module = @import("Module.zig");
-const ir = @import("ir.zig");
+
+const std = @import("std");
+
+const Inst = @import("ir.zig").Inst;
 const Value = @import("value.zig").Value;
 const Type = @import("type.zig").Type;
-const std = @import("std");
 
 const C = link.File.C;
 const Decl = Module.Decl;
@@ -45,159 +47,159 @@ fn renderFunctionSignature(file: *C, writer: std.ArrayList(u8).Writer, decl: *De
     const name = try map(file.allocator, mem.spanZ(decl.name));
     defer file.allocator.free(name);
     try writer.print(" {}(", .{name});
-    if (tv.ty.fnParamLen() == 0) {
-        try writer.writeAll("void)");
-    } else {
+    if (tv.ty.fnParamLen() == 0)
+        try writer.writeAll("void)")
+    else
         return file.fail(decl.src(), "TODO implement parameters", .{});
-    }
 }
 
 pub fn generate(file: *C, decl: *Decl) !void {
+    switch (decl.typed_value.most_recent.typed_value.ty.zigTypeTag()) {
+        .Fn => try genFn(file, decl),
+        .Array => try genArray(file, decl),
+        else => |e| return file.fail(decl.src(), "TODO {}", .{e}),
+    }
+}
+
+fn genArray(file: *C, decl: *Decl) !void {
+    const tv = decl.typed_value.most_recent.typed_value;
+    // TODO: prevent inline asm constants from being emitted
+    const name = try map(file.allocator, mem.span(decl.name));
+    defer file.allocator.free(name);
+    if (tv.val.cast(Value.Payload.Bytes)) |payload|
+        if (tv.ty.arraySentinel()) |sentinel|
+            if (sentinel.toUnsignedInt() == 0)
+                try file.constants.writer().print("const char *const {} = \"{}\";\n", .{ name, payload.data })
+            else
+                return file.fail(decl.src(), "TODO byte arrays with non-zero sentinels", .{})
+        else
+            return file.fail(decl.src(), "TODO byte arrays without sentinels", .{})
+    else
+        return file.fail(decl.src(), "TODO non-byte arrays", .{});
+}
+
+fn genFn(file: *C, decl: *Decl) !void {
     const writer = file.main.writer();
-    const header = file.header.writer();
     const tv = decl.typed_value.most_recent.typed_value;
-    switch (tv.ty.zigTypeTag()) {
-        .Fn => {
-            try renderFunctionSignature(file, writer, decl);
-
-            try writer.writeAll(" {");
-
-            const func: *Module.Fn = tv.val.cast(Value.Payload.Function).?.func;
-            const instructions = func.analysis.success.instructions;
-            if (instructions.len > 0) {
-                for (instructions) |inst| {
-                    try writer.writeAll("\n\t");
-                    switch (inst.tag) {
-                        .assembly => {
-                            const as = inst.cast(ir.Inst.Assembly).?.args;
-                            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];
-                                    if (arg.cast(ir.Inst.Constant)) |c| {
-                                        if (c.val.tag() == .int_u64) {
-                                            try writer.writeAll("register ");
-                                            try renderType(file, writer, arg.ty, decl.src());
-                                            try writer.print(" {}_constant __asm__(\"{}\") = {};\n\t", .{ reg, reg, c.val.toUnsignedInt() });
-                                        } else {
-                                            return file.fail(decl.src(), "TODO inline asm {} args", .{c.val.tag()});
-                                        }
-                                    } else {
-                                        return file.fail(decl.src(), "TODO non-constant inline asm args", .{});
-                                    }
-                                } else {
-                                    return file.fail(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", .{});
-                            }
-                            if (as.inputs.len > 0) {
-                                if (as.output == null) {
-                                    try writer.writeAll(" :");
-                                }
-                                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];
-                                        if (index > 0) {
-                                            try writer.writeAll(", ");
-                                        }
-                                        if (arg.cast(ir.Inst.Constant)) |c| {
-                                            try writer.print("\"\"({}_constant)", .{reg});
-                                        } else {
-                                            // This is blocked by the earlier test
-                                            unreachable;
-                                        }
-                                    } else {
-                                        // This is blocked by the earlier test
-                                        unreachable;
-                                    }
-                                }
-                            }
-                            try writer.writeAll(");");
-                        },
-                        .call => {
-                            const call = inst.cast(ir.Inst.Call).?;
-                            if (call.args.func.cast(ir.Inst.Constant)) |func_inst| {
-                                if (func_inst.val.cast(Value.Payload.Function)) |func_val| {
-                                    const target = func_val.func.owner_decl;
-                                    const target_ty = target.typed_value.most_recent.typed_value.ty;
-                                    const ret_ty = target_ty.fnReturnType().tag();
-                                    if (target_ty.fnReturnType().hasCodeGenBits() and call.base.isUnused()) {
-                                        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);
-                                        try header.writeAll(";\n");
-                                    }
-                                    try writer.print("{}();", .{tname});
-                                } else {
-                                    return file.fail(decl.src(), "TODO non-function call target?", .{});
-                                }
-                                if (call.args.args.len != 0) {
-                                    return file.fail(decl.src(), "TODO function arguments", .{});
-                                }
-                            } else {
-                                return file.fail(decl.src(), "TODO non-constant call inst?", .{});
-                            }
-                        },
-                        .ret => {
-                            const ret_value: *ir.Inst = inst.cast(ir.Inst.Ret).?.args.operand;
-                            const expected_return_type = tv.ty.fnReturnType();
-                            const value = ret_value.value().?;
-                            if (expected_return_type.eql(ret_value.ty)) {
-                                return file.fail(decl.src(), "TODO return {}", .{expected_return_type});
-                            } else {
-                                if (expected_return_type.isInt() and ret_value.ty.tag() == .comptime_int) {
-                                    if (value.intFitsInType(expected_return_type, file.options.target)) {
-                                        if (expected_return_type.intInfo(file.options.target).bits <= 64) {
-                                            try writer.print("return {};", .{value.toUnsignedInt()});
-                                        } else {
-                                            return file.fail(decl.src(), "TODO return ints > 64 bits", .{});
-                                        }
-                                    } else {
-                                        return file.fail(decl.src(), "comptime int {} does not fit in {}", .{ value.toUnsignedInt(), expected_return_type });
-                                    }
-                                } else {
-                                    return file.fail(decl.src(), "return type mismatch: expected {}, found {}", .{ expected_return_type, ret_value.ty });
-                                }
-                            }
-                        },
-                        else => |e| {
-                            return file.fail(decl.src(), "TODO {}", .{e});
-                        },
-                    }
-                }
-                try writer.writeAll("\n");
+
+    try renderFunctionSignature(file, writer, decl);
+
+    try writer.writeAll(" {");
+
+    const func: *Module.Fn = tv.val.cast(Value.Payload.Function).?.func;
+    const instructions = func.analysis.success.instructions;
+    if (instructions.len > 0) {
+        for (instructions) |inst| {
+            try writer.writeAll("\n\t");
+            switch (inst.tag) {
+                .assembly => try genAsm(file, inst.cast(Inst.Assembly).?, decl),
+                .call => try genCall(file, inst.cast(Inst.Call).?, decl),
+                .ret => try genRet(file, inst.cast(Inst.Ret).?, decl, tv.ty.fnReturnType()),
+                else => |e| return file.fail(decl.src(), "TODO {}", .{e}),
+            }
+        }
+        try writer.writeAll("\n");
+    }
+
+    try writer.writeAll("}\n\n");
+}
+
+fn genRet(file: *C, inst: *Inst.Ret, decl: *Decl, expected_return_type: Type) !void {
+    const writer = file.main.writer();
+    const ret_value = inst.args.operand;
+    const value = ret_value.value().?;
+    if (expected_return_type.eql(ret_value.ty))
+        return file.fail(decl.src(), "TODO return {}", .{expected_return_type})
+    else if (expected_return_type.isInt() and ret_value.ty.tag() == .comptime_int)
+        if (value.intFitsInType(expected_return_type, file.options.target))
+            if (expected_return_type.intInfo(file.options.target).bits <= 64)
+                try writer.print("return {};", .{value.toUnsignedInt()})
+            else
+                return file.fail(decl.src(), "TODO return ints > 64 bits", .{})
+        else
+            return file.fail(decl.src(), "comptime int {} does not fit in {}", .{ value.toUnsignedInt(), expected_return_type })
+    else
+        return file.fail(decl.src(), "return type mismatch: expected {}, found {}", .{ expected_return_type, ret_value.ty });
+}
+
+fn genCall(file: *C, inst: *Inst.Call, decl: *Decl) !void {
+    const writer = file.main.writer();
+    const header = file.header.writer();
+    if (inst.args.func.cast(Inst.Constant)) |func_inst| {
+        if (func_inst.val.cast(Value.Payload.Function)) |func_val| {
+            const target = func_val.func.owner_decl;
+            const target_ty = target.typed_value.most_recent.typed_value.ty;
+            const ret_ty = target_ty.fnReturnType().tag();
+            if (target_ty.fnReturnType().hasCodeGenBits() and inst.base.isUnused()) {
+                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);
+                try header.writeAll(";\n");
+            }
+            try writer.print("{}();", .{tname});
+        } else {
+            return file.fail(decl.src(), "TODO non-function call target?", .{});
+        }
+        if (inst.args.args.len != 0) {
+            return file.fail(decl.src(), "TODO function arguments", .{});
+        }
+    } else {
+        return file.fail(decl.src(), "TODO non-constant call inst?", .{});
+    }
+}
 
-            try writer.writeAll("}\n\n");
-        },
-        .Array => {
-            // TODO: prevent inline asm constants from being emitted
-            const name = try map(file.allocator, mem.span(decl.name));
-            defer file.allocator.free(name);
-            if (tv.val.cast(Value.Payload.Bytes)) |payload| {
-                if (tv.ty.arraySentinel()) |sentinel| {
-                    if (sentinel.toUnsignedInt() == 0) {
-                        try file.constants.writer().print("const char *const {} = \"{}\";\n", .{ name, payload.data });
-                    } else {
-                        return file.fail(decl.src(), "TODO byte arrays with non-zero sentinels", .{});
-                    }
+fn genAsm(file: *C, inst: *Inst.Assembly, decl: *Decl) !void {
+    const as = inst.args;
+    const writer = file.main.writer();
+    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];
+            if (arg.cast(Inst.Constant)) |c| {
+                if (c.val.tag() == .int_u64) {
+                    try writer.writeAll("register ");
+                    try renderType(file, writer, arg.ty, decl.src());
+                    try writer.print(" {}_constant __asm__(\"{}\") = {};\n\t", .{ reg, reg, c.val.toUnsignedInt() });
                 } else {
-                    return file.fail(decl.src(), "TODO byte arrays without sentinels", .{});
+                    return file.fail(decl.src(), "TODO inline asm {} args", .{c.val.tag()});
                 }
             } else {
-                return file.fail(decl.src(), "TODO non-byte arrays", .{});
+                return file.fail(decl.src(), "TODO non-constant inline asm args", .{});
             }
-        },
-        else => |e| {
-            return file.fail(decl.src(), "TODO {}", .{e});
-        },
+        } else {
+            return file.fail(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", .{});
+    }
+    if (as.inputs.len > 0) {
+        if (as.output == null) {
+            try writer.writeAll(" :");
+        }
+        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];
+                if (index > 0) {
+                    try writer.writeAll(", ");
+                }
+                if (arg.cast(Inst.Constant)) |c| {
+                    try writer.print("\"\"({}_constant)", .{reg});
+                } else {
+                    // This is blocked by the earlier test
+                    unreachable;
+                }
+            } else {
+                // This is blocked by the earlier test
+                unreachable;
+            }
+        }
     }
+    try writer.writeAll(");");
 }