x86_64: misc fixes

src/codegen/x86_64/CodeGen.zig

@@ -179000,7 +179000,14 @@ fn genSetMem(
         .reg => |base_reg| .{ .register_offset = .{ .reg = base_reg, .off = disp } },
         .frame => |base_frame_index| .{ .lea_frame = .{ .index = base_frame_index, .off = disp } },
         .table, .rip_inst, .lazy_sym => unreachable,
-        .nav => |nav| .{ .lea_nav = nav },
+        .nav => |nav| {
+            // hack around linker relocation bugs
+            const addr_reg = try self.copyToTmpRegister(.usize, .{ .lea_nav = nav });
+            const addr_lock = self.register_manager.lockRegAssumeUnused(addr_reg);
+            defer self.register_manager.unlockReg(addr_lock);
+
+            return self.genSetMem(.{ .reg = addr_reg }, disp, ty, src_mcv, opts);
+        },
         .uav => |uav| .{ .lea_uav = uav },
         .extern_func => |extern_func| .{ .lea_extern_func = extern_func },
     };

src/codegen/x86_64/Encoding.zig

@@ -297,7 +297,7 @@ pub const Mnemonic = enum {
     jnc, jne, jng, jnge, jnl, jnle, jno, jnp, jns, jnz, jo, jp, jpe, jpo, jrcxz, js, jz,
     lahf, lar, lea, leave, lfence, lgdt, lidt, lldt, lmsw, loop, loope, loopne,
     lods, lodsb, lodsd, lodsq, lodsw,
-    lsl, ltr,
+    lret, lsl, ltr,
     mfence, mov, movbe,
     movs, movsb, movsd, movsq, movsw,
     movsx, movsxd, movzx, mul,

src/codegen/x86_64/Mir.zig

@@ -1732,7 +1732,7 @@ pub const Inst = struct {
             assert(@sizeOf(Data) == 8);
         }
         const Mnemonic = @import("Encoding.zig").Mnemonic;
-        if (@typeInfo(Mnemonic).@"enum".fields.len != 977 or
+        if (@typeInfo(Mnemonic).@"enum".fields.len != 978 or
             @typeInfo(Fixes).@"enum".fields.len != 231 or
             @typeInfo(Tag).@"enum".fields.len != 251)
         {
@@ -1741,7 +1741,7 @@ pub const Inst = struct {
                     return @src();
                 }
             }).src();
-            @setEvalBranchQuota(1_750_000);
+            @setEvalBranchQuota(2_000_000);
             for (@typeInfo(Mnemonic).@"enum".fields) |mnemonic| {
                 if (mnemonic.name[0] == '.') continue;
                 for (@typeInfo(Fixes).@"enum".fields) |fixes| {

src/codegen/x86_64/encodings.zon

@@ -459,6 +459,8 @@
     .{ .loope,  .d, .{ .rel8 }, .{ 0xe1 }, 0, .none, .none },
     .{ .loopne, .d, .{ .rel8 }, .{ 0xe0 }, 0, .none, .none },
 
+    .{ .lret, .z, .{}, .{ 0xcb }, 0, .none, .none },
+
     .{ .lsl, .rm, .{ .r16, .rm16    }, .{ 0x0f, 0x03 }, 0, .none, .none },
     .{ .lsl, .rm, .{ .r32, .r32_m16 }, .{ 0x0f, 0x03 }, 0, .none, .none },
     .{ .lsl, .rm, .{ .r64, .r32_m16 }, .{ 0x0f, 0x03 }, 0, .none, .none },

test/behavior/memset.zig

@@ -179,3 +179,14 @@ test "@memset with zero-length array" {
     var array: [0]usize = undefined;
     @memset(&array, 0);
 }
+
+test "@memset a global array" {
+    const S = struct {
+        var buf: [1]u32 = .{123};
+    };
+    try expect(S.buf[0] == 123);
+    @memset(&S.buf, 456);
+    try expect(S.buf[0] == 456);
+    @memset(&S.buf, S.buf[0] + 333);
+    try expect(S.buf[0] == 789);
+}