Commit 025611629f

Jacob Young <jacobly0@users.noreply.github.com>
2025-05-12 15:13:20
x86_64: implement `@memmove`
1 parent 6d68a49
Changed files (3)
src/arch/x86_64/CodeGen.zig
@@ -101399,8 +101399,66 @@ fn genBody(cg: *CodeGen, body: []const Air.Inst.Index) InnerError!void {
 
             .memset => try cg.airMemset(inst, false),
             .memset_safe => try cg.airMemset(inst, true),
-            .memcpy => try cg.airMemcpy(inst),
-            .memmove => try cg.airMemmove(inst),
+            .memcpy, .memmove => |air_tag| if (use_old) switch (air_tag) {
+                else => unreachable,
+                .memcpy => try cg.airMemcpy(inst),
+                .memmove => return cg.fail("TODO implement airMemmove for {}", .{cg.target.cpu.arch}),
+            } else {
+                const bin_op = air_datas[@intFromEnum(inst)].bin_op;
+                var ops = try cg.tempsFromOperands(inst, .{ bin_op.lhs, bin_op.rhs }) ++ .{undefined};
+                ops[2] = ops[0].getByteLen(cg) catch |err| switch (err) {
+                    error.SelectFailed => return cg.fail("failed to select {s} {} {} {} {}", .{
+                        @tagName(air_tag),
+                        cg.typeOf(bin_op.lhs).fmt(pt),
+                        cg.typeOf(bin_op.rhs).fmt(pt),
+                        ops[0].tracking(cg),
+                        ops[1].tracking(cg),
+                    }),
+                    else => |e| return e,
+                };
+                try ops[0].toSlicePtr(cg);
+                cg.select(&.{}, &.{}, &ops, switch (air_tag) {
+                    else => unreachable,
+                    inline .memcpy, .memmove => |symbol| comptime &.{.{
+                        .patterns = &.{
+                            .{ .src = .{
+                                .{ .to_param_gpr = .{ .cc = .ccc, .index = 0 } },
+                                .{ .to_param_gpr = .{ .cc = .ccc, .index = 1 } },
+                                .{ .to_param_gpr = .{ .cc = .ccc, .index = 2 } },
+                            } },
+                        },
+                        .call_frame = .{ .alignment = .@"16" },
+                        .extra_temps = .{
+                            .{ .type = .usize, .kind = .{ .symbol = &.{ .name = @tagName(symbol) } } },
+                            .unused,
+                            .unused,
+                            .unused,
+                            .unused,
+                            .unused,
+                            .unused,
+                            .unused,
+                            .unused,
+                            .unused,
+                            .unused,
+                        },
+                        .clobbers = .{ .eflags = true, .caller_preserved = .ccc },
+                        .each = .{ .once = &.{
+                            .{ ._, ._, .call, .tmp0d, ._, ._, ._ },
+                        } },
+                    }},
+                }) catch |err| switch (err) {
+                    error.SelectFailed => return cg.fail("failed to select {s} {} {} {} {} {}", .{
+                        @tagName(air_tag),
+                        cg.typeOf(bin_op.lhs).fmt(pt),
+                        cg.typeOf(bin_op.rhs).fmt(pt),
+                        ops[0].tracking(cg),
+                        ops[1].tracking(cg),
+                        ops[2].tracking(cg),
+                    }),
+                    else => |e| return e,
+                };
+                for (ops) |op| try op.die(cg);
+            },
             .cmpxchg_weak, .cmpxchg_strong => try cg.airCmpxchg(inst),
             .atomic_load => try cg.airAtomicLoad(inst),
             .atomic_store_unordered => try cg.airAtomicStore(inst, .unordered),
@@ -118458,11 +118516,6 @@ fn airMemcpy(self: *CodeGen, inst: Air.Inst.Index) !void {
     return self.finishAir(inst, .unreach, .{ bin_op.lhs, bin_op.rhs, .none });
 }
 
-fn airMemmove(self: *CodeGen, inst: Air.Inst.Index) !void {
-    _ = inst;
-    return self.fail("TODO implement airMemmove for {}", .{self.target.cpu.arch});
-}
-
 fn airTagName(self: *CodeGen, inst: Air.Inst.Index, only_safety: bool) !void {
     const pt = self.pt;
     const zcu = pt.zcu;
@@ -122137,6 +122190,49 @@ const Temp = struct {
         return .{ .index = new_temp_index.toIndex() };
     }
 
+    fn getByteLen(temp: *Temp, cg: *CodeGen) Select.Error!Temp {
+        const zcu = cg.pt.zcu;
+        const ip = &zcu.intern_pool;
+        const ptr_info = ip.indexToKey(temp.typeOf(cg).toIntern()).ptr_type;
+        switch (ptr_info.flags.size) {
+            .one => {
+                const array_info = ip.indexToKey(ptr_info.child).array_type;
+                return cg.tempInit(.usize, .{
+                    .immediate = Type.fromInterned(array_info.child).abiSize(zcu) * array_info.len,
+                });
+            },
+            .many, .c => unreachable,
+            .slice => {
+                const elem_size = Type.fromInterned(ptr_info.child).abiSize(zcu);
+                var len = try temp.getLimb(.usize, 1, cg);
+                while (try len.toRegClass(true, .general_purpose, cg)) {}
+                const len_reg = len.tracking(cg).short.register.to64();
+                if (!std.math.isPowerOfTwo(elem_size)) {
+                    try cg.spillEflagsIfOccupied();
+                    try cg.asmRegisterRegisterImmediate(
+                        .{ .i_, .mul },
+                        len_reg,
+                        len_reg,
+                        .u(elem_size),
+                    );
+                } else if (elem_size > 8) {
+                    try cg.spillEflagsIfOccupied();
+                    try cg.asmRegisterImmediate(
+                        .{ ._l, .sh },
+                        len_reg,
+                        .u(std.math.log2_int(u64, elem_size)),
+                    );
+                } else if (elem_size != 1) try cg.asmRegisterMemory(.{ ._, .lea }, len_reg, .{
+                    .mod = .{ .rm = .{
+                        .index = len_reg,
+                        .scale = .fromFactor(@intCast(elem_size)),
+                    } },
+                });
+                return len;
+            },
+        }
+    }
+
     fn toLimb(temp: *Temp, limb_ty: Type, limb_index: u28, cg: *CodeGen) InnerError!void {
         switch (temp.unwrap(cg)) {
             .ref => {},
test/behavior/builtin_functions_returning_void_or_noreturn.zig
@@ -6,7 +6,6 @@ var x: u8 = 1;
 
 // This excludes builtin functions that return void or noreturn that cannot be tested.
 test {
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
test/behavior/memmove.zig
@@ -3,13 +3,13 @@ const builtin = @import("builtin");
 const expect = std.testing.expect;
 
 test "memmove and memset intrinsics" {
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
     if (builtin.zig_backend == .stage2_spirv64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_riscv64) return error.SkipZigTest;
+    if (builtin.zig_backend == .stage2_x86_64 and builtin.target.ofmt != .elf and builtin.target.ofmt != .macho) return error.SkipZigTest;
 
     try testMemmoveMemset();
     try comptime testMemmoveMemset();
@@ -33,13 +33,13 @@ fn testMemmoveMemset() !void {
 }
 
 test "@memmove with both operands single-ptr-to-array, one is null-terminated" {
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_spirv64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_riscv64) return error.SkipZigTest;
+    if (builtin.zig_backend == .stage2_x86_64 and builtin.target.ofmt != .elf and builtin.target.ofmt != .macho) return error.SkipZigTest;
 
     try testMemmoveBothSinglePtrArrayOneIsNullTerminated();
     try comptime testMemmoveBothSinglePtrArrayOneIsNullTerminated();
@@ -79,13 +79,13 @@ fn testMemmoveBothSinglePtrArrayOneIsNullTerminated() !void {
 }
 
 test "@memmove dest many pointer" {
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_spirv64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_riscv64) return error.SkipZigTest;
+    if (builtin.zig_backend == .stage2_x86_64 and builtin.target.ofmt != .elf and builtin.target.ofmt != .macho) return error.SkipZigTest;
 
     try testMemmoveDestManyPtr();
     try comptime testMemmoveDestManyPtr();
@@ -123,13 +123,13 @@ fn testMemmoveDestManyPtr() !void {
 }
 
 test "@memmove slice" {
-    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_spirv64) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest;
     if (builtin.zig_backend == .stage2_riscv64) return error.SkipZigTest;
+    if (builtin.zig_backend == .stage2_x86_64 and builtin.target.ofmt != .elf and builtin.target.ofmt != .macho) return error.SkipZigTest;
 
     try testMemmoveSlice();
     try comptime testMemmoveSlice();