Merge branch 'shawnl-lessThan'

 * always allow integer comparison operations no matter the
   bit width, signedness, or comptime-ness of operands.
   closes #2133
 * implement comparisons for vectors, which returns vector of
   bools.

closes #3001

2 files changed, 43 insertions, 33 deletions

diff --git a/test/compile_errors.zig b/test/compile_errors.zig
index d48aaa1125..c826d45cea 100644
--- a/test/compile_errors.zig
+++ b/test/compile_errors.zig
@@ -4174,58 +4174,50 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
         "tmp.zig:3:5: error: use of undefined value here causes undefined behavior",
     });
 
-    cases.add("equal on undefined value",
+    cases.add("comparison operators with undefined value",
+        \\// operator ==
         \\comptime {
         \\    var a: i64 = undefined;
-        \\    _ = a == a;
+        \\    var x: i32 = 0;
+        \\    if (a == a) x += 1;
         \\}
-    , &[_][]const u8{
-        "tmp.zig:3:9: error: use of undefined value here causes undefined behavior",
-    });
-
-    cases.add("not equal on undefined value",
+        \\// operator !=
         \\comptime {
         \\    var a: i64 = undefined;
-        \\    _ = a != a;
+        \\    var x: i32 = 0;
+        \\    if (a != a) x += 1;
         \\}
-    , &[_][]const u8{
-        "tmp.zig:3:9: error: use of undefined value here causes undefined behavior",
-    });
-
-    cases.add("greater than on undefined value",
+        \\// operator >
         \\comptime {
         \\    var a: i64 = undefined;
-        \\    _ = a > a;
+        \\    var x: i32 = 0;
+        \\    if (a > a) x += 1;
         \\}
-    , &[_][]const u8{
-        "tmp.zig:3:9: error: use of undefined value here causes undefined behavior",
-    });
-
-    cases.add("greater than equal on undefined value",
+        \\// operator <
         \\comptime {
         \\    var a: i64 = undefined;
-        \\    _ = a >= a;
+        \\    var x: i32 = 0;
+        \\    if (a < a) x += 1;
         \\}
-    , &[_][]const u8{
-        "tmp.zig:3:9: error: use of undefined value here causes undefined behavior",
-    });
-
-    cases.add("less than on undefined value",
+        \\// operator >=
         \\comptime {
         \\    var a: i64 = undefined;
-        \\    _ = a < a;
+        \\    var x: i32 = 0;
+        \\    if (a >= a) x += 1;
         \\}
-    , &[_][]const u8{
-        "tmp.zig:3:9: error: use of undefined value here causes undefined behavior",
-    });
-
-    cases.add("less than equal on undefined value",
+        \\// operator <=
         \\comptime {
         \\    var a: i64 = undefined;
-        \\    _ = a <= a;
+        \\    var x: i32 = 0;
+        \\    if (a <= a) x += 1;
         \\}
     , &[_][]const u8{
-        "tmp.zig:3:9: error: use of undefined value here causes undefined behavior",
+        "tmp.zig:5:11: error: use of undefined value here causes undefined behavior",
+        "tmp.zig:11:11: error: use of undefined value here causes undefined behavior",
+        "tmp.zig:17:11: error: use of undefined value here causes undefined behavior",
+        "tmp.zig:23:11: error: use of undefined value here causes undefined behavior",
+        "tmp.zig:29:11: error: use of undefined value here causes undefined behavior",
+        "tmp.zig:35:11: error: use of undefined value here causes undefined behavior",
     });
 
     cases.add("and on undefined value",
diff --git a/test/stage1/behavior/math.zig b/test/stage1/behavior/math.zig
index 751275aeb6..3a73e776eb 100644
--- a/test/stage1/behavior/math.zig
+++ b/test/stage1/behavior/math.zig
@@ -4,6 +4,7 @@ const expectEqual = std.testing.expectEqual;
 const expectEqualSlices = std.testing.expectEqualSlices;
 const maxInt = std.math.maxInt;
 const minInt = std.math.minInt;
+const mem = std.mem;
 
 test "division" {
     if (@import("builtin").arch == .riscv64) {
@@ -653,3 +654,20 @@ test "128-bit multiplication" {
     var c = a * b;
     expect(c == 6);
 }
+
+test "vector comparison" {
+    const S = struct {
+        fn doTheTest() void {
+            var a: @Vector(6, i32) = [_]i32{1, 3, -1, 5, 7, 9};
+            var b: @Vector(6, i32) = [_]i32{-1, 3, 0, 6, 10, -10};
+            expect(mem.eql(bool, &@as([6]bool, a < b), &[_]bool{false, false, true, true, true, false}));
+            expect(mem.eql(bool, &@as([6]bool, a <= b), &[_]bool{false, true, true, true, true, false}));
+            expect(mem.eql(bool, &@as([6]bool, a == b), &[_]bool{false, true, false, false, false, false}));
+            expect(mem.eql(bool, &@as([6]bool, a != b), &[_]bool{true, false, true, true, true, true}));
+            expect(mem.eql(bool, &@as([6]bool, a > b), &[_]bool{true, false, false, false, false, true}));
+            expect(mem.eql(bool, &@as([6]bool, a >= b), &[_]bool{true, true, false, false, false, true}));
+        }
+    };
+    S.doTheTest();
+    comptime S.doTheTest();
+}