Commit c41ac8f19ec96ed854d9ac31a2015006ba3e4657 | zig

author	Andrew Kelley <andrew@ziglang.org> 2025-07-22 06:29:58+02:00
committer	GitHub <noreply@github.com> 2025-07-22 06:29:58+02:00
log	c41ac8f19ec96ed854d9ac31a2015006ba3e4657
tree	125fb5b12917b1f7b8405f594470f54f33d6bff3
parent	9abc3232a8c02f0fc6bef6ad0bad56a3804e6bc3
parent	7d02b693beeb53fa7f69c55301d8c5f5581b23b2
signature	Signed by PGP key B5690EEEBB952194

Merge pull request #24534 from ziglang/fix-missed-opvs

Sema: fix missed simplifications of OPVs

1 files changed, 33 insertions(+), 6 deletions(-)

src
- Sema.zig

src/Sema.zig+33-6

 @@ -5000,9 +5000,11 @@ fn validateUnionInit(
     }
     if (init_ref) |v| try sema.validateRuntimeValue(block, block.nodeOffset(field_ptr_data.src_node), v);
-    const new_tag = Air.internedToRef(tag_val.toIntern());
+    if ((try sema.typeHasOnePossibleValue(tag_ty)) == null) {
-    const set_tag_inst = try block.addBinOp(.set_union_tag, union_ptr, new_tag);
+        const new_tag = Air.internedToRef(tag_val.toIntern());
-    try sema.checkComptimeKnownStore(block, set_tag_inst, LazySrcLoc.unneeded); // `unneeded` since this isn't a "proper" store
+        const set_tag_inst = try block.addBinOp(.set_union_tag, union_ptr, new_tag);
+        try sema.checkComptimeKnownStore(block, set_tag_inst, LazySrcLoc.unneeded); // `unneeded` since this isn't a "proper" store
+    }
 }
 fn validateStructInit(
 @@ -6560,6 +6562,11 @@ fn resolveAnalyzedBlock(
             } },
         });
     }
+    if (try sema.typeHasOnePossibleValue(resolved_ty)) |block_only_value| {
+        return Air.internedToRef(block_only_value.toIntern());
+    }
     return merges.block_inst.toRef();
 }
 @@ -9056,6 +9063,10 @@ fn analyzeErrUnionPayload(
         try sema.addSafetyCheckUnwrapError(block, src, operand, .unwrap_errunion_err, .is_non_err);
     }
+    if (try sema.typeHasOnePossibleValue(payload_ty)) |payload_only_value| {
+        return Air.internedToRef(payload_only_value.toIntern());
+    }
     return block.addTyOp(.unwrap_errunion_payload, payload_ty, operand);
 }
 @@ -19690,8 +19701,10 @@ fn zirStructInit(
             const base_ptr = try sema.optEuBasePtrInit(block, alloc, src);
             const field_ptr = try sema.unionFieldPtr(block, field_src, base_ptr, field_name, field_src, resolved_ty, true);
             try sema.storePtr(block, src, field_ptr, init_inst);
-            const new_tag = Air.internedToRef(tag_val.toIntern());
+            if ((try sema.typeHasOnePossibleValue(tag_ty)) == null) {
-            _ = try block.addBinOp(.set_union_tag, base_ptr, new_tag);
+                const new_tag = Air.internedToRef(tag_val.toIntern());
+                _ = try block.addBinOp(.set_union_tag, base_ptr, new_tag);
+            }
             return sema.makePtrConst(block, alloc);
         }
 @@ -28079,10 +28092,16 @@ fn unionFieldVal(
         const active_tag = try block.addTyOp(.get_union_tag, .fromInterned(union_obj.enum_tag_ty), union_byval);
         try sema.addSafetyCheckInactiveUnionField(block, src, active_tag, wanted_tag);
     }
     if (field_ty.zigTypeTag(zcu) == .noreturn) {
         _ = try block.addNoOp(.unreach);
         return .unreachable_value;
     }
+    if (try sema.typeHasOnePossibleValue(field_ty)) |field_only_value| {
+        return Air.internedToRef(field_only_value.toIntern());
+    }
     try field_ty.resolveLayout(pt);
     return block.addStructFieldVal(union_byval, field_index, field_ty);
 }
 @@ -28214,12 +28233,12 @@ fn elemVal(
             .many, .c => {
                 const maybe_indexable_val = try sema.resolveDefinedValue(block, indexable_src, indexable);
                 const maybe_index_val = try sema.resolveDefinedValue(block, elem_index_src, elem_index);
+                const elem_ty = indexable_ty.elemType2(zcu);
                 ct: {
                     const indexable_val = maybe_indexable_val orelse break :ct;
                     const index_val = maybe_index_val orelse break :ct;
                     const index: usize = @intCast(try index_val.toUnsignedIntSema(pt));
-                    const elem_ty = indexable_ty.elemType2(zcu);
                     const many_ptr_ty = try pt.manyConstPtrType(elem_ty);
                     const many_ptr_val = try pt.getCoerced(indexable_val, many_ptr_ty);
                     const elem_ptr_ty = try pt.singleConstPtrType(elem_ty);
 @@ -28228,6 +28247,10 @@ fn elemVal(
                     return Air.internedToRef((try pt.getCoerced(elem_val, elem_ty)).toIntern());
                 }
+                if (try sema.typeHasOnePossibleValue(elem_ty)) |elem_only_value| {
+                    return Air.internedToRef(elem_only_value.toIntern());
+                }
                 try sema.checkLogicalPtrOperation(block, src, indexable_ty);
                 return block.addBinOp(.ptr_elem_val, indexable, elem_index);
             },
 @@ -28578,6 +28601,10 @@ fn elemValSlice(
         }
     }
+    if (try sema.typeHasOnePossibleValue(elem_ty)) |elem_only_value| {
+        return Air.internedToRef(elem_only_value.toIntern());
+    }
     try sema.validateRuntimeElemAccess(block, elem_index_src, elem_ty, slice_ty, slice_src);
     try sema.validateRuntimeValue(block, slice_src, slice);