Commit `b4d6e85a33`

Andrew Kelley <andrew@ziglang.org>

2022-01-02 22:11:37

Sema: implement peer type resolution of signed and unsigned ints

This allows stage2 to build more of compiler-rt. I also changed `-%` to `-` for comptime ints in the div and mul implementations of compiler-rt. This is clearer code and also happens to work around a bug in stage2.

master

1 parent 6b14c58

Changed files (9)

lib

std

special

compiler_rt

src

test

behavior

cast.zig

cast_stage1.zig

@@ -35,7 +35,7 @@ pub fn __divdf3(a: f64, b: f64) callconv(.C) f64 {
     var scale: i32 = 0;
 
     // Detect if a or b is zero, denormal, infinity, or NaN.
-    if (aExponent -% 1 >= maxExponent -% 1 or bExponent -% 1 >= maxExponent -% 1) {
+    if (aExponent -% 1 >= maxExponent - 1 or bExponent -% 1 >= maxExponent - 1) {
         const aAbs: Z = @bitCast(Z, a) & absMask;
         const bAbs: Z = @bitCast(Z, b) & absMask;

@@ -34,7 +34,7 @@ pub fn __divsf3(a: f32, b: f32) callconv(.C) f32 {
     var scale: i32 = 0;
 
     // Detect if a or b is zero, denormal, infinity, or NaN.
-    if (aExponent -% 1 >= maxExponent -% 1 or bExponent -% 1 >= maxExponent -% 1) {
+    if (aExponent -% 1 >= maxExponent - 1 or bExponent -% 1 >= maxExponent - 1) {
         const aAbs: Z = @bitCast(Z, a) & absMask;
         const bAbs: Z = @bitCast(Z, b) & absMask;

@@ -33,7 +33,7 @@ pub fn __divtf3(a: f128, b: f128) callconv(.C) f128 {
     var scale: i32 = 0;
 
     // Detect if a or b is zero, denormal, infinity, or NaN.
-    if (aExponent -% 1 >= maxExponent -% 1 or bExponent -% 1 >= maxExponent -% 1) {
+    if (aExponent -% 1 >= maxExponent - 1 or bExponent -% 1 >= maxExponent - 1) {
         const aAbs: Z = @bitCast(Z, a) & absMask;
         const bAbs: Z = @bitCast(Z, b) & absMask;

@@ -56,7 +56,7 @@ fn mulXf3(comptime T: type, a: T, b: T) T {
     var scale: i32 = 0;
 
     // Detect if a or b is zero, denormal, infinity, or NaN.
-    if (aExponent -% 1 >= maxExponent -% 1 or bExponent -% 1 >= maxExponent -% 1) {
+    if (aExponent -% 1 >= maxExponent - 1 or bExponent -% 1 >= maxExponent - 1) {
         const aAbs: Z = @bitCast(Z, a) & absMask;
         const bAbs: Z = @bitCast(Z, b) & absMask;

@@ -221,21 +221,19 @@ comptime {
     const __subtf3 = @import("compiler_rt/addXf3.zig").__subtf3;
     @export(__subtf3, .{ .name = "__subtf3", .linkage = linkage });
 
-    if (!builtin.zig_is_stage2) {
-        const __mulsf3 = @import("compiler_rt/mulXf3.zig").__mulsf3;
-        @export(__mulsf3, .{ .name = "__mulsf3", .linkage = linkage });
-        const __muldf3 = @import("compiler_rt/mulXf3.zig").__muldf3;
-        @export(__muldf3, .{ .name = "__muldf3", .linkage = linkage });
-        const __multf3 = @import("compiler_rt/mulXf3.zig").__multf3;
-        @export(__multf3, .{ .name = "__multf3", .linkage = linkage });
-
-        const __divsf3 = @import("compiler_rt/divsf3.zig").__divsf3;
-        @export(__divsf3, .{ .name = "__divsf3", .linkage = linkage });
-        const __divdf3 = @import("compiler_rt/divdf3.zig").__divdf3;
-        @export(__divdf3, .{ .name = "__divdf3", .linkage = linkage });
-        const __divtf3 = @import("compiler_rt/divtf3.zig").__divtf3;
-        @export(__divtf3, .{ .name = "__divtf3", .linkage = linkage });
-    }
+    const __mulsf3 = @import("compiler_rt/mulXf3.zig").__mulsf3;
+    @export(__mulsf3, .{ .name = "__mulsf3", .linkage = linkage });
+    const __muldf3 = @import("compiler_rt/mulXf3.zig").__muldf3;
+    @export(__muldf3, .{ .name = "__muldf3", .linkage = linkage });
+    const __multf3 = @import("compiler_rt/mulXf3.zig").__multf3;
+    @export(__multf3, .{ .name = "__multf3", .linkage = linkage });
+
+    const __divsf3 = @import("compiler_rt/divsf3.zig").__divsf3;
+    @export(__divsf3, .{ .name = "__divsf3", .linkage = linkage });
+    const __divdf3 = @import("compiler_rt/divdf3.zig").__divdf3;
+    @export(__divdf3, .{ .name = "__divdf3", .linkage = linkage });
+    const __divtf3 = @import("compiler_rt/divtf3.zig").__divtf3;
+    @export(__divtf3, .{ .name = "__divtf3", .linkage = linkage });
 
     // Integral bit manipulation
     const __ashldi3 = @import("compiler_rt/shift.zig").__ashldi3;
@@ -251,26 +249,24 @@ comptime {
     const __lshrti3 = @import("compiler_rt/shift.zig").__lshrti3;
     @export(__lshrti3, .{ .name = "__lshrti3", .linkage = linkage });
 
-    if (!builtin.zig_is_stage2) {
-        const __clzsi2 = @import("compiler_rt/count0bits.zig").__clzsi2;
-        @export(__clzsi2, .{ .name = "__clzsi2", .linkage = linkage });
-        const __clzdi2 = @import("compiler_rt/count0bits.zig").__clzdi2;
-        @export(__clzdi2, .{ .name = "__clzdi2", .linkage = linkage });
-        const __clzti2 = @import("compiler_rt/count0bits.zig").__clzti2;
-        @export(__clzti2, .{ .name = "__clzti2", .linkage = linkage });
-        const __ctzsi2 = @import("compiler_rt/count0bits.zig").__ctzsi2;
-        @export(__ctzsi2, .{ .name = "__ctzsi2", .linkage = linkage });
-        const __ctzdi2 = @import("compiler_rt/count0bits.zig").__ctzdi2;
-        @export(__ctzdi2, .{ .name = "__ctzdi2", .linkage = linkage });
-        const __ctzti2 = @import("compiler_rt/count0bits.zig").__ctzti2;
-        @export(__ctzti2, .{ .name = "__ctzti2", .linkage = linkage });
-        const __ffssi2 = @import("compiler_rt/count0bits.zig").__ffssi2;
-        @export(__ffssi2, .{ .name = "__ffssi2", .linkage = linkage });
-        const __ffsdi2 = @import("compiler_rt/count0bits.zig").__ffsdi2;
-        @export(__ffsdi2, .{ .name = "__ffsdi2", .linkage = linkage });
-        const __ffsti2 = @import("compiler_rt/count0bits.zig").__ffsti2;
-        @export(__ffsti2, .{ .name = "__ffsti2", .linkage = linkage });
-    }
+    const __clzsi2 = @import("compiler_rt/count0bits.zig").__clzsi2;
+    @export(__clzsi2, .{ .name = "__clzsi2", .linkage = linkage });
+    const __clzdi2 = @import("compiler_rt/count0bits.zig").__clzdi2;
+    @export(__clzdi2, .{ .name = "__clzdi2", .linkage = linkage });
+    const __clzti2 = @import("compiler_rt/count0bits.zig").__clzti2;
+    @export(__clzti2, .{ .name = "__clzti2", .linkage = linkage });
+    const __ctzsi2 = @import("compiler_rt/count0bits.zig").__ctzsi2;
+    @export(__ctzsi2, .{ .name = "__ctzsi2", .linkage = linkage });
+    const __ctzdi2 = @import("compiler_rt/count0bits.zig").__ctzdi2;
+    @export(__ctzdi2, .{ .name = "__ctzdi2", .linkage = linkage });
+    const __ctzti2 = @import("compiler_rt/count0bits.zig").__ctzti2;
+    @export(__ctzti2, .{ .name = "__ctzti2", .linkage = linkage });
+    const __ffssi2 = @import("compiler_rt/count0bits.zig").__ffssi2;
+    @export(__ffssi2, .{ .name = "__ffssi2", .linkage = linkage });
+    const __ffsdi2 = @import("compiler_rt/count0bits.zig").__ffsdi2;
+    @export(__ffsdi2, .{ .name = "__ffsdi2", .linkage = linkage });
+    const __ffsti2 = @import("compiler_rt/count0bits.zig").__ffsti2;
+    @export(__ffsti2, .{ .name = "__ffsti2", .linkage = linkage });
 
     const __paritysi2 = @import("compiler_rt/parity.zig").__paritysi2;
     @export(__paritysi2, .{ .name = "__paritysi2", .linkage = linkage });

@@ -14634,11 +14634,11 @@ fn resolvePeerTypes(
     instructions: []Air.Inst.Ref,
     candidate_srcs: Module.PeerTypeCandidateSrc,
 ) !Type {
-    if (instructions.len == 0)
-        return Type.initTag(.noreturn);
-
-    if (instructions.len == 1)
-        return sema.typeOf(instructions[0]);
+    switch (instructions.len) {
+        0 => return Type.initTag(.noreturn),
+        1 => return sema.typeOf(instructions[0]),
+        else => {},
+    }
 
     const target = sema.mod.getTarget();
 
@@ -14668,13 +14668,14 @@ fn resolvePeerTypes(
                     continue;
                 },
                 .Int => {
-                    if (chosen_ty.isSignedInt() == candidate_ty.isSignedInt()) {
-                        if (chosen_ty.intInfo(target).bits < candidate_ty.intInfo(target).bits) {
-                            chosen = candidate;
-                            chosen_i = candidate_i + 1;
-                        }
-                        continue;
+                    const chosen_info = chosen_ty.intInfo(target);
+                    const candidate_info = candidate_ty.intInfo(target);
+
+                    if (chosen_info.bits < candidate_info.bits) {
+                        chosen = candidate;
+                        chosen_i = candidate_i + 1;
                     }
+                    continue;
                 },
                 .Pointer => if (chosen_ty.ptrSize() == .C) continue,
                 else => {},

@@ -3106,9 +3106,9 @@ pub const Type = extern union {
             .c_ulonglong => return .{ .signedness = .unsigned, .bits = CType.ulonglong.sizeInBits(target) },
 
             .enum_full, .enum_nonexhaustive => ty = ty.cast(Payload.EnumFull).?.data.tag_ty,
-            .enum_numbered => ty = self.castTag(.enum_numbered).?.data.tag_ty,
+            .enum_numbered => ty = ty.castTag(.enum_numbered).?.data.tag_ty,
             .enum_simple => {
-                const enum_obj = self.castTag(.enum_simple).?.data;
+                const enum_obj = ty.castTag(.enum_simple).?.data;
                 const field_count = enum_obj.fields.count();
                 if (field_count == 0) return .{ .signedness = .unsigned, .bits = 0 };
                 return .{ .signedness = .unsigned, .bits = smallestUnsignedBits(field_count - 1) };

@@ -295,3 +295,12 @@ test "cast from ?[*]T to ??[*]T" {
     const a: ??[*]u8 = @as(?[*]u8, null);
     try expect(a != null and a.? == null);
 }
+
+test "peer type unsigned int to signed" {
+    var w: u31 = 5;
+    var x: u8 = 7;
+    var y: i32 = -5;
+    var a = w + y + x;
+    comptime try expect(@TypeOf(a) == i32);
+    try expect(a == 7);
+}

@@ -383,15 +383,6 @@ test "peer type resolve string lit with sentinel-terminated mutable slice" {
     comptime try expect(@TypeOf("hi", slice) == [:0]const u8);
 }
 
-test "peer type unsigned int to signed" {
-    var w: u31 = 5;
-    var x: u8 = 7;
-    var y: i32 = -5;
-    var a = w + y + x;
-    comptime try expect(@TypeOf(a) == i32);
-    try expect(a == 7);
-}
-
 test "peer type resolve array pointers, one of them const" {
     var array1: [4]u8 = undefined;
     const array2: [5]u8 = undefined;

Commit b4d6e85a33

Commit `b4d6e85a33`