| author |  Justus Klausecker <justus@klausecker.de> 2025-08-07 02:08:40+02:00 |
| committer | Justus Klausecker <justus@klausecker.de> 2025-08-12 16:33:57+02:00 |
| log | 0ef26d113ae5a8b307a3af76db61706846fea22f |
| tree | 2caf4a84834fbc2059f851629ff9933ca0dc3cae |
| parent | d0586da18e08d0b8bdc2347fabdc0ba531901641 |
make `>>` a compile error with any undef arg ; add a bunch of test cases
8 files changed, 65 insertions(+), 32 deletions(-)
src/Sema.zig+7-15
| ... | ... | @@ -13826,11 +13826,9 @@ fn zirShr( |
| 13826 | 13826 | else => unreachable, |
| 13827 | 13827 | })).toIntern()); |
| 13828 | 13828 | } |
| 13829 | if (rhs_val.isUndef(zcu)) switch (air_tag) { | |
| 13830 | .shr => return pt.undefRef(lhs_ty), | |
| 13831 | .shr_exact => return sema.failWithUseOfUndef(block, rhs_src, null), | |
| 13832 | else => unreachable, | |
| 13833 | }; | |
| 13829 | if (rhs_val.isUndef(zcu)) { | |
| 13830 | return sema.failWithUseOfUndef(block, rhs_src, null); | |
| 13831 | } | |
| 13834 | 13832 | const bits_val = try pt.intValue(.comptime_int, scalar_ty.intInfo(zcu).bits); |
| 13835 | 13833 | switch (rhs_ty.zigTypeTag(zcu)) { |
| 13836 | 13834 | .int, .comptime_int => { |
| ... | ... | @@ -13849,11 +13847,9 @@ fn zirShr( |
| 13849 | 13847 | var elem_idx: usize = 0; |
| 13850 | 13848 | while (elem_idx < rhs_ty.vectorLen(zcu)) : (elem_idx += 1) { |
| 13851 | 13849 | const rhs_elem = try rhs_val.elemValue(pt, elem_idx); |
| 13852 | if (rhs_elem.isUndef(zcu)) switch (air_tag) { | |
| 13853 | .shr => continue, | |
| 13854 | .shr_exact => return sema.failWithUseOfUndef(block, rhs_src, elem_idx), | |
| 13855 | else => unreachable, | |
| 13856 | }; | |
| 13850 | if (rhs_elem.isUndef(zcu)) { | |
| 13851 | return sema.failWithUseOfUndef(block, rhs_src, elem_idx); | |
| 13852 | } | |
| 13857 | 13853 | switch (try rhs_elem.orderAgainstZeroSema(pt)) { |
| 13858 | 13854 | .gt => { |
| 13859 | 13855 | if (try rhs_elem.compareHeteroSema(.gte, bits_val, pt)) { |
| ... | ... | @@ -13875,11 +13871,7 @@ fn zirShr( |
| 13875 | 13871 | return sema.fail(block, src, "LHS of shift must be a fixed-width integer type, or RHS must be comptime-known", .{}); |
| 13876 | 13872 | } |
| 13877 | 13873 | if (maybe_lhs_val) |lhs_val| { |
| 13878 | switch (air_tag) { | |
| 13879 | .shr => if (lhs_val.isUndef(zcu)) return pt.undefRef(lhs_ty), | |
| 13880 | .shr_exact => try sema.checkAllScalarsDefined(block, lhs_src, lhs_val), | |
| 13881 | else => unreachable, | |
| 13882 | } | |
| 13874 | try sema.checkAllScalarsDefined(block, lhs_src, lhs_val); | |
| 13883 | 13875 | } |
| 13884 | 13876 | } |
| 13885 | 13877 | break :rs rhs_src; |
src/Sema/arith.zig+3-10
| ... | ... | @@ -1221,16 +1221,9 @@ fn shrScalar( |
| 1221 | 1221 | const pt = sema.pt; |
| 1222 | 1222 | const zcu = pt.zcu; |
| 1223 | 1223 | |
| 1224 | switch (op) { | |
| 1225 | .shr => { | |
| 1226 | if (lhs_val.isUndef(zcu)) return lhs_val; | |
| 1227 | if (rhs_val.isUndef(zcu)) return pt.undefValue(lhs_ty); | |
| 1228 | }, | |
| 1229 | .shr_exact => { | |
| 1230 | if (lhs_val.isUndef(zcu)) return sema.failWithUseOfUndef(block, lhs_src, vec_idx); | |
| 1231 | if (rhs_val.isUndef(zcu)) return sema.failWithUseOfUndef(block, rhs_src, vec_idx); | |
| 1232 | }, | |
| 1233 | } | |
| 1224 | if (lhs_val.isUndef(zcu)) return sema.failWithUseOfUndef(block, lhs_src, vec_idx); | |
| 1225 | if (rhs_val.isUndef(zcu)) return sema.failWithUseOfUndef(block, rhs_src, vec_idx); | |
| 1226 | ||
| 1234 | 1227 | switch (try rhs_val.orderAgainstZeroSema(pt)) { |
| 1235 | 1228 | .gt => {}, |
| 1236 | 1229 | .eq => return lhs_val, |
test/behavior/bit_shifting.zig-7
| ... | ... | @@ -196,10 +196,3 @@ test "Saturating Shift Left" { |
| 196 | 196 | try expectEqual(170141183460469231731687303715884105727, S.shlSat(@as(i128, 0x2fe6bc5448c55ce18252e2c9d4477750), 0x31)); |
| 197 | 197 | try expectEqual(0, S.shlSat(@as(i128, 0), 127)); |
| 198 | 198 | } |
| 199 | ||
| 200 | test "shift by partially undef vector" { | |
| 201 | comptime { | |
| 202 | const a: @Vector(1, u8) = .{undefined}; | |
| 203 | _ = a >> @splat(4); | |
| 204 | } | |
| 205 | } |
test/cases/compile_errors/shl_exact_on_undefined_value.zig created+11
| ... | ... | @@ -0,0 +1,11 @@ |
| 1 | comptime { | |
| 2 | var a: i64 = undefined; | |
| 3 | var b: u6 = undefined; | |
| 4 | _ = &a; | |
| 5 | _ = &b; | |
| 6 | _ = @shlExact(a, b); | |
| 7 | } | |
| 8 | ||
| 9 | // error | |
| 10 | // | |
| 11 | // :6:19: error: use of undefined value here causes illegal behavior |
test/cases/compile_errors/shl_on_undefined_value.zig created+11
| ... | ... | @@ -0,0 +1,11 @@ |
| 1 | comptime { | |
| 2 | var a: i64 = undefined; | |
| 3 | var b: u6 = undefined; | |
| 4 | _ = &a; | |
| 5 | _ = &b; | |
| 6 | _ = a << b; | |
| 7 | } | |
| 8 | ||
| 9 | // error | |
| 10 | // | |
| 11 | // :6:9: error: use of undefined value here causes illegal behavior |
test/cases/compile_errors/shl_with_overflow_on_undefined_value.zig created+11
| ... | ... | @@ -0,0 +1,11 @@ |
| 1 | comptime { | |
| 2 | var a: i64 = undefined; | |
| 3 | var b: u6 = undefined; | |
| 4 | _ = &a; | |
| 5 | _ = &b; | |
| 6 | _ = @shlWithOverflow(a, b); | |
| 7 | } | |
| 8 | ||
| 9 | // error | |
| 10 | // | |
| 11 | // :6:26: error: use of undefined value here causes illegal behavior |
test/cases/compile_errors/shr_exact_on_undefined_value.zig created+11
| ... | ... | @@ -0,0 +1,11 @@ |
| 1 | comptime { | |
| 2 | var a: i64 = undefined; | |
| 3 | var b: u6 = undefined; | |
| 4 | _ = &a; | |
| 5 | _ = &b; | |
| 6 | _ = @shrExact(a, b); | |
| 7 | } | |
| 8 | ||
| 9 | // error | |
| 10 | // | |
| 11 | // :6:19: error: use of undefined value here causes illegal behavior |
test/cases/compile_errors/shr_on_undefined_value.zig created+11
| ... | ... | @@ -0,0 +1,11 @@ |
| 1 | comptime { | |
| 2 | var a: i64 = undefined; | |
| 3 | var b: u6 = undefined; | |
| 4 | _ = &a; | |
| 5 | _ = &b; | |
| 6 | _ = a >> b; | |
| 7 | } | |
| 8 | ||
| 9 | // error | |
| 10 | // | |
| 11 | // :6:9: error: use of undefined value here causes illegal behavior |