Commit ac2211118f
Changed files (2)
src/codegen.zig
@@ -1783,8 +1783,8 @@ fn Function(comptime arch: std.Target.Cpu.Arch) type {
switch (mc_arg) {
.none => continue,
.register => |reg| {
+ try self.register_manager.getRegWithoutTracking(reg);
try self.genSetReg(arg.src, arg.ty, reg, arg_mcv);
- // TODO interact with the register allocator to mark the instruction as moved.
},
.stack_offset => {
// Here we need to emit instructions like this:
@@ -1925,8 +1925,8 @@ fn Function(comptime arch: std.Target.Cpu.Arch) type {
.compare_flags_signed => unreachable,
.compare_flags_unsigned => unreachable,
.register => |reg| {
+ try self.register_manager.getRegWithoutTracking(reg);
try self.genSetReg(arg.src, arg.ty, reg, arg_mcv);
- // TODO interact with the register allocator to mark the instruction as moved.
},
.stack_offset => {
return self.fail(inst.base.src, "TODO implement calling with parameters in memory", .{});
@@ -1988,8 +1988,8 @@ fn Function(comptime arch: std.Target.Cpu.Arch) type {
.compare_flags_signed => unreachable,
.compare_flags_unsigned => unreachable,
.register => |reg| {
+ try self.register_manager.getRegWithoutTracking(reg);
try self.genSetReg(arg.src, arg.ty, reg, arg_mcv);
- // TODO interact with the register allocator to mark the instruction as moved.
},
.stack_offset => {
return self.fail(inst.base.src, "TODO implement calling with parameters in memory", .{});
@@ -2039,8 +2039,8 @@ fn Function(comptime arch: std.Target.Cpu.Arch) type {
switch (mc_arg) {
.none => continue,
.register => |reg| {
+ try self.register_manager.getRegWithoutTracking(reg);
try self.genSetReg(arg.src, arg.ty, reg, arg_mcv);
- // TODO interact with the register allocator to mark the instruction as moved.
},
.stack_offset => {
// Here we need to emit instructions like this:
@@ -2704,8 +2704,11 @@ fn Function(comptime arch: std.Target.Cpu.Arch) type {
const reg_name = input[1 .. input.len - 1];
const reg = parseRegName(reg_name) orelse
return self.fail(inst.base.src, "unrecognized register: '{s}'", .{reg_name});
- const arg = try self.resolveInst(inst.args[i]);
- try self.genSetReg(inst.base.src, inst.args[i].ty, reg, arg);
+
+ const arg = inst.args[i];
+ const arg_mcv = try self.resolveInst(arg);
+ try self.register_manager.getRegWithoutTracking(reg);
+ try self.genSetReg(inst.base.src, arg.ty, reg, arg_mcv);
}
if (mem.eql(u8, inst.asm_source, "svc #0")) {
@@ -2734,8 +2737,11 @@ fn Function(comptime arch: std.Target.Cpu.Arch) type {
const reg_name = input[1 .. input.len - 1];
const reg = parseRegName(reg_name) orelse
return self.fail(inst.base.src, "unrecognized register: '{s}'", .{reg_name});
- const arg = try self.resolveInst(inst.args[i]);
- try self.genSetReg(inst.base.src, inst.args[i].ty, reg, arg);
+
+ const arg = inst.args[i];
+ const arg_mcv = try self.resolveInst(arg);
+ try self.register_manager.getRegWithoutTracking(reg);
+ try self.genSetReg(inst.base.src, arg.ty, reg, arg_mcv);
}
if (mem.eql(u8, inst.asm_source, "svc #0")) {
@@ -2766,8 +2772,11 @@ fn Function(comptime arch: std.Target.Cpu.Arch) type {
const reg_name = input[1 .. input.len - 1];
const reg = parseRegName(reg_name) orelse
return self.fail(inst.base.src, "unrecognized register: '{s}'", .{reg_name});
- const arg = try self.resolveInst(inst.args[i]);
- try self.genSetReg(inst.base.src, inst.args[i].ty, reg, arg);
+
+ const arg = inst.args[i];
+ const arg_mcv = try self.resolveInst(arg);
+ try self.register_manager.getRegWithoutTracking(reg);
+ try self.genSetReg(inst.base.src, arg.ty, reg, arg_mcv);
}
if (mem.eql(u8, inst.asm_source, "ecall")) {
@@ -2796,8 +2805,11 @@ fn Function(comptime arch: std.Target.Cpu.Arch) type {
const reg_name = input[1 .. input.len - 1];
const reg = parseRegName(reg_name) orelse
return self.fail(inst.base.src, "unrecognized register: '{s}'", .{reg_name});
- const arg = try self.resolveInst(inst.args[i]);
- try self.genSetReg(inst.base.src, inst.args[i].ty, reg, arg);
+
+ const arg = inst.args[i];
+ const arg_mcv = try self.resolveInst(arg);
+ try self.register_manager.getRegWithoutTracking(reg);
+ try self.genSetReg(inst.base.src, arg.ty, reg, arg_mcv);
}
if (mem.eql(u8, inst.asm_source, "syscall")) {
src/register_manager.zig
@@ -35,6 +35,10 @@ pub fn RegisterManager(
self.registers.deinit(allocator);
}
+ fn isTracked(reg: Register) bool {
+ return std.mem.indexOfScalar(Register, callee_preserved_regs, reg) != null;
+ }
+
fn markRegUsed(self: *Self, reg: Register) void {
if (FreeRegInt == u0) return;
const index = reg.allocIndex() orelse return;
@@ -51,6 +55,13 @@ pub fn RegisterManager(
self.free_registers |= @as(FreeRegInt, 1) << shift;
}
+ pub fn isRegFree(self: Self, reg: Register) bool {
+ if (FreeRegInt == u0) return true;
+ const index = reg.allocIndex() orelse return true;
+ const shift = @intCast(ShiftInt, index);
+ return self.free_registers & @as(FreeRegInt, 1) << shift != 0;
+ }
+
/// Returns whether this register was allocated in the course
/// of this function
pub fn isRegAllocated(self: Self, reg: Register) bool {
@@ -117,17 +128,59 @@ pub fn RegisterManager(
const regs_entry = self.registers.remove(reg).?;
const spilled_inst = regs_entry.value;
try self.getFunction().spillInstruction(spilled_inst.src, reg, spilled_inst);
+ self.markRegFree(reg);
break :b reg;
};
}
+ /// Allocates the specified register with the specified
+ /// instruction. Spills the register if it is currently
+ /// allocated.
+ pub fn getReg(self: *Self, reg: Register, inst: *ir.Inst) !void {
+ if (!isTracked(reg)) return;
+
+ if (!self.isRegFree(reg)) {
+ // Move the instruction that was previously there to a
+ // stack allocation.
+ const regs_entry = self.registers.getEntry(reg).?;
+ const spilled_inst = regs_entry.value;
+ regs_entry.value = inst;
+ try self.getFunction().spillInstruction(spilled_inst.src, reg, spilled_inst);
+ } else {
+ try self.getRegAssumeFree(reg, inst);
+ }
+ }
+
+ /// Spills the register if it is currently allocated.
+ /// Does not track the register.
+ pub fn getRegWithoutTracking(self: *Self, reg: Register) !void {
+ if (!isTracked(reg)) return;
+
+ if (!self.isRegFree(reg)) {
+ // Move the instruction that was previously there to a
+ // stack allocation.
+ const regs_entry = self.registers.getEntry(reg).?;
+ const spilled_inst = regs_entry.value;
+ try self.getFunction().spillInstruction(spilled_inst.src, reg, spilled_inst);
+ self.markRegFree(reg);
+ }
+ }
+
+ /// Allocates the specified register with the specified
+ /// instruction. Assumes that the register is free and no
+ /// spilling is necessary.
pub fn getRegAssumeFree(self: *Self, reg: Register, inst: *ir.Inst) !void {
+ if (!isTracked(reg)) return;
+
try self.registers.putNoClobber(self.getFunction().gpa, reg, inst);
self.markRegUsed(reg);
}
+ /// Marks the specified register as free
pub fn freeReg(self: *Self, reg: Register) void {
+ if (!isTracked(reg)) return;
+
_ = self.registers.remove(reg);
self.markRegFree(reg);
}