From 8c553d6565ee1ff6d7679e65f7958c36a5858522 Mon Sep 17 00:00:00 2001 From: Graham Nelson Date: Mon, 4 Oct 2021 23:35:07 +0100 Subject: [PATCH] Tentative movement of property storage policy into assembly --- docs/BasicInformKit/S-rtp.html | 108 +++---- docs/final-module/2-cg.html | 12 +- docs/final-module/2-cg2.html | 2 +- docs/final-module/2-tvg.html | 2 +- docs/final-module/4-fi6.html | 147 ++++++++- docs/runtime-module/5-prp.html | 117 +++---- inform7/Figures/memory-diagnostics.txt | 16 +- inform7/Figures/timings-diagnostics.txt | 30 +- .../Inter/BasicInformKit/Sections/RTP.i6t | 108 +++---- inform7/Tests/Test Makes/Eg4-C/textual.txt | 294 +++++++----------- inform7/runtime-module/Chapter 5/Properties.w | 104 +++---- inter/final-module/Chapter 4/Final Inform 6.w | 115 +++++++ 12 files changed, 574 insertions(+), 481 deletions(-) diff --git a/docs/BasicInformKit/S-rtp.html b/docs/BasicInformKit/S-rtp.html index 73d208dea..fe076da75 100644 --- a/docs/BasicInformKit/S-rtp.html +++ b/docs/BasicInformKit/S-rtp.html @@ -303,41 +303,40 @@ it doesn't mean it actually does have. 

-[ WhetherProvides K obj q issue_rtp  a l holder;
-    if (K ~= OBJECT_TY) {
-        if ((obj < 1) || (obj > value_ranges-->K)) {
-            if (issue_rtp) RunTimeProblem(RTP_BADVALUEPROPERTY);
-            rfalse;
-        } else {
-            holder = value_property_holders-->K;
-            if ((holder) && (holder provides q)) rtrue;
+[ ProvidesProperty K obj q issue_rtp  a l holder;
+    if (K == OBJECT_TY) {
+        if (ScanPropertyMetadata(obj, q, 4)) jump PermissionFound;
+        if (obj provides KD_Count) {
+            l = obj.KD_Count;
+            while (l > 0) {
+                a = l*2;
+                if (ScanPropertyMetadata(KindHierarchy-->a, q, 4)) jump PermissionFound;
+                l = KindHierarchy-->(a+1);
+            }
         }
-    }
-    if (obj == 0) {
-        if (issue_rtp) RunTimeProblem(RTP_PROPOFNOTHING, 0, q);
+        if (ScanPropertyMetadata(K0_kind, q, 4)) jump PermissionFound;
+        if (issue_rtp) RunTimeProblem(RTP_UNPROVIDED, obj, q);
         rfalse;
     }
-    if (metaclass(obj) ~= Object) rfalse;
-    if (q<0) q = ~q;
-
-    if (ScanPropertyMetadata(obj, q, 4)) jump PermissionFound;
-    if (obj provides KD_Count) {
-        l = obj.KD_Count;
-        while (l > 0) {
-            a = l*2;
-            if (ScanPropertyMetadata(KindHierarchy-->a, q, 4)) jump PermissionFound;
-            l = KindHierarchy-->(a+1);
-        }
-    }
-    if (ScanPropertyMetadata(K0_kind, q, 4)) jump PermissionFound;
-    if (issue_rtp) RunTimeProblem(RTP_UNPROVIDED, obj, q);
-    rfalse;
 
     .PermissionFound;
-        if (q-->2) rtrue;
-        if (obj provides q) rtrue;
-        if (issue_rtp) RunTimeProblem(RTP_UNSET, obj, q);
-        rfalse;
+
+    @provides_gprop K obj q a;
+    if (a) rtrue;
+if (K ~= OBJECT_TY) {
+	if ((obj >= 1) && (obj <= value_ranges-->K)) {
+		holder = value_property_holders-->K;
+		if ((holder) && (holder provides q)) rtrue;
+	}
+} else {
+	if ((obj) && (metaclass(obj) == Object)) {
+		if (q-->0 == 2) rtrue;
+		if (obj provides q) rtrue;
+	}
+}
+
+    if (issue_rtp) RunTimeProblem(RTP_UNSET, obj, q);
+    rfalse;
 ];
 
 [ PrintPropertyName  p  textual;
@@ -375,18 +374,20 @@ the one which the player is on.
 

 
 
-[ GProperty K V pr err holder;
-    if (WhetherProvides(K, V, pr, 1-err)) {
-        if (K == OBJECT_TY) {
-            if (pr-->0 == 2) {
-                if (V has pr) rtrue; rfalse;
-            }
-            if (pr == door_to) return V.pr();
-            return V.pr;
-        } else {
-            holder = value_property_holders-->K;
-            return (holder.pr)-->(V+COL_HSIZE);
-        }
+[ GProperty K V pr err holder val;
+    if (ProvidesProperty(K, V, pr, 1-err)) {
+        @read_gprop K V pr val;
+        return val;
+	if (K == OBJECT_TY) {
+		if (pr-->0 == 2) {
+			if (V has pr) rtrue; rfalse;
+		}
+		if (pr == door_to) return V.pr();
+		return V.pr;
+	} else {
+		holder = value_property_holders-->K;
+		return (holder.pr)-->(V+COL_HSIZE);
+	}
     }
     return 0;
 ];
@@ -398,17 +399,18 @@ converted from an rvalue to an lvalue.
 
 
 [ WriteGProperty K V pr val holder;
-    if (WhetherProvides(K, V, pr, true)) {
-        if (K == OBJECT_TY) {
-            if (pr-->0 == 2) {
-                if (val) give V pr; else give V ~pr;
-            } else {
-                V.pr = val;
-            }
-        } else {
-            holder = value_property_holders-->K;
-            (holder.pr)-->(V+COL_HSIZE) = val;
-        }
+    if (ProvidesProperty(K, V, pr, true)) {
+        @write_gprop K V pr val;
+	if (K == OBJECT_TY) {
+		if (pr-->0 == 2) {
+			if (val) give V pr; else give V ~pr;
+		} else {
+			V.pr = val;
+		}
+	} else {
+		holder = value_property_holders-->K;
+		(holder.pr)-->(V+COL_HSIZE) = val;
+	}
     }
 ];
 

diff --git a/docs/final-module/2-cg.html b/docs/final-module/2-cg.html
index 9c750a932..99a7234c6 100644
--- a/docs/final-module/2-cg.html
+++ b/docs/final-module/2-cg.html
@@ -334,7 +334,7 @@ but for now about 10 layers is plenty.
 

 
 
-segmentation_pos CodeGen::select(code_generation *gen, int i) {
+segmentation_pos CodeGen::select(code_generation *gen, int i) {
     return CodeGen::select_layered(gen, i, 1);
 }
 
@@ -351,7 +351,7 @@ but for now about 10 layers is plenty.
     return previous_pos;
 }
 
-void CodeGen::deselect(code_generation *gen, segmentation_pos saved) {
+void CodeGen::deselect(code_generation *gen, segmentation_pos saved) {
     if (gen->segmentation.temporarily_diverted) internal_error("poorly timed deselection");
     gen->segmentation.pos = saved;
 }
@@ -361,13 +361,13 @@ some temporary stream somewhere. For that, use the following pair:
 

 
 
-void CodeGen::select_temporary(code_generation *gen, text_stream *T) {
+void CodeGen::select_temporary(code_generation *gen, text_stream *T) {
     if (gen->segmentation.temporarily_diverted) internal_error("nested temporary segments");
     gen->segmentation.temporarily_diverted_to = T;
     gen->segmentation.temporarily_diverted = TRUE;
 }
 
-void CodeGen::deselect_temporary(code_generation *gen) {
+void CodeGen::deselect_temporary(code_generation *gen) {
     gen->segmentation.temporarily_diverted_to = NULL;
     gen->segmentation.temporarily_diverted = FALSE;
 }
@@ -377,7 +377,7 @@ if it has been "temporarily diverted" then the regiular selection is ignored.
 

 
 
-text_stream *CodeGen::current(code_generation *gen) {
+text_stream *CodeGen::current(code_generation *gen) {
     if (gen->segmentation.temporarily_diverted)
         return gen->segmentation.temporarily_diverted_to;
     if (gen->segmentation.pos.current_segment == NULL) return NULL;
@@ -453,7 +453,7 @@ extracted from some Inter instruction.
     Generate from a value pair15.1;
 }
 
-void CodeGen::pair(code_generation *gen, inter_tree_node *P,
+void CodeGen::pair(code_generation *gen, inter_tree_node *P,
     inter_ti val1, inter_ti val2) {
     inter_symbols_table *T = P?(Inter::Packages::scope_of(P)):NULL;
     Generate from a value pair15.1;
diff --git a/docs/final-module/2-cg2.html b/docs/final-module/2-cg2.html
index 28d3fc018..f736613f1 100644
--- a/docs/final-module/2-cg2.html
+++ b/docs/final-module/2-cg2.html
@@ -233,7 +233,7 @@ I6 code. Still, all pragmas are offered to all generators.
 

 
 VOID_METHOD_TYPE(MANGLE_IDENTIFIER_MTID, code_generator *generator, text_stream *OUT, text_stream *identifier)
-void Generators::mangle(code_generation *gen, text_stream *OUT, text_stream *identifier) {
+void Generators::mangle(code_generation *gen, text_stream *OUT, text_stream *identifier) {
     VOID_METHOD_CALL(gen->generator, MANGLE_IDENTIFIER_MTID, OUT, identifier);
 }
 

diff --git a/docs/final-module/2-tvg.html b/docs/final-module/2-tvg.html
index a81209a25..137e0d4bf 100644
--- a/docs/final-module/2-tvg.html
+++ b/docs/final-module/2-tvg.html
@@ -254,7 +254,7 @@ well the entire tree by the end.
 define VNODE_ALLC  LOOP_THROUGH_INTER_CHILDREN(C, P) Vanilla::node(gen, C)
 

 
-void Vanilla::node(code_generation *gen, inter_tree_node *P) {
+void Vanilla::node(code_generation *gen, inter_tree_node *P) {
     switch (P->W.data[ID_IFLD]) {
         case CONSTANT_IST:      VanillaConstants::constant(gen, P); break;
 
diff --git a/docs/final-module/4-fi6.html b/docs/final-module/4-fi6.html
index 576fc1f17..c9850abaf 100644
--- a/docs/final-module/4-fi6.html
+++ b/docs/final-module/4-fi6.html
@@ -146,15 +146,15 @@ function togglePopup(material_id) {
     METHOD_ADD(cgt, EVALUATE_LABEL_MTID, I6Target::evaluate_label);
     METHOD_ADD(cgt, INVOKE_FUNCTION_MTID, I6Target::invoke_function);
     METHOD_ADD(cgt, INVOKE_OPCODE_MTID, I6Target::invoke_opcode);
-    METHOD_ADD(cgt, BEGIN_ARRAY_MTID, I6Target::begin_array);
-    METHOD_ADD(cgt, ARRAY_ENTRY_MTID, I6Target::array_entry);
-    METHOD_ADD(cgt, COMPILE_LITERAL_SYMBOL_MTID, I6Target::compile_literal_symbol);
-    METHOD_ADD(cgt, ARRAY_ENTRIES_MTID, I6Target::array_entries);
-    METHOD_ADD(cgt, END_ARRAY_MTID, I6Target::end_array);
+    METHOD_ADD(cgt, BEGIN_ARRAY_MTID, I6Target::begin_array);
+    METHOD_ADD(cgt, ARRAY_ENTRY_MTID, I6Target::array_entry);
+    METHOD_ADD(cgt, COMPILE_LITERAL_SYMBOL_MTID, I6Target::compile_literal_symbol);
+    METHOD_ADD(cgt, ARRAY_ENTRIES_MTID, I6Target::array_entries);
+    METHOD_ADD(cgt, END_ARRAY_MTID, I6Target::end_array);
     METHOD_ADD(cgt, OFFER_PRAGMA_MTID, I6Target::offer_pragma)
     METHOD_ADD(cgt, END_GENERATION_MTID, I6Target::end_generation);
-    METHOD_ADD(cgt, PSEUDO_OBJECT_MTID, I6Target::pseudo_object);
-    METHOD_ADD(cgt, NEW_ACTION_MTID, I6Target::new_action);
+    METHOD_ADD(cgt, PSEUDO_OBJECT_MTID, I6Target::pseudo_object);
+    METHOD_ADD(cgt, NEW_ACTION_MTID, I6Target::new_action);
     inform6_target = cgt;
 }
 

@@ -1405,6 +1405,9 @@ or implement assembly-language operations like     text_stream *opcode, int operand_count, inter_tree_node **operands,
     inter_tree_node *label, int label_sense, int void_context) {
     text_stream *OUT = CodeGen::current(gen);
+    if (Str::eq(opcode, I"@provides_gprop")) Invoke special provides_gprop9.1;
+    if (Str::eq(opcode, I"@read_gprop")) Invoke special read_gprop9.2;
+    if (Str::eq(opcode, I"@write_gprop")) Invoke special write_gprop9.3;
     WRITE("%S", opcode);
     for (int opc = 0; opc < operand_count; opc++) {
         WRITE(" ");
@@ -1417,7 +1420,133 @@ or implement assembly-language operations like     }
     if (void_context) WRITE(";\n");
 }
+

+
§9.1.  Invoke special provides_gprop9.1 =
+

 
+
+    TEMPORARY_TEXT(K)
+    TEMPORARY_TEXT(obj)
+    TEMPORARY_TEXT(p)
+    TEMPORARY_TEXT(val)
+    CodeGen::select_temporary(gen, K);
+    Vanilla::node(gen, operands[0]);
+    CodeGen::deselect_temporary(gen);
+    CodeGen::select_temporary(gen, obj);
+    Vanilla::node(gen, operands[1]);
+    CodeGen::deselect_temporary(gen);
+    CodeGen::select_temporary(gen, p);
+    Vanilla::node(gen, operands[2]);
+    CodeGen::deselect_temporary(gen);
+    CodeGen::select_temporary(gen, val);
+    Vanilla::node(gen, operands[3]);
+    CodeGen::deselect_temporary(gen);
+
+    WRITE("if (%S == OBJECT_TY) {\n", K);
+    WRITE("    if ((%S) && (metaclass(%S) == Object)) {\n", obj, obj);
+    WRITE("        if ((%S-->0 == 2) || (%S provides %S-->1)) {\n", p, obj, p);
+    WRITE("            %S = 1;\n", val);
+    WRITE("        } else {\n");
+    WRITE("            %S = 0;\n", val);
+    WRITE("        }\n");
+    WRITE("    } else {\n");
+    WRITE("        %S = 0;\n", val);
+    WRITE("    }\n");
+    WRITE("} else {\n");
+    WRITE("    if ((%S >= 1) && (%S <= value_ranges-->%S)) {\n", obj, obj, K);
+    WRITE("        holder = value_property_holders-->%S;\n", K);
+    WRITE("        if ((holder) && (holder provides %S-->1)) {\n", p);
+    WRITE("            %S = 1;\n", val);
+    WRITE("        } else {\n");
+    WRITE("            %S = 0;\n", val);
+    WRITE("        }\n");
+    WRITE("    } else {\n");
+    WRITE("        %S = 0;\n", val);
+    WRITE("    }\n");
+    WRITE("}\n");
+
+    DISCARD_TEXT(K)
+    DISCARD_TEXT(obj)
+    DISCARD_TEXT(p)
+    DISCARD_TEXT(val)
+    return;
+

+
  • This code is used in §9.

+
§9.2.  Invoke special read_gprop9.2 =
+

+
+
+    TEMPORARY_TEXT(K)
+    TEMPORARY_TEXT(obj)
+    TEMPORARY_TEXT(p)
+    CodeGen::select_temporary(gen, K);
+    Vanilla::node(gen, operands[0]);
+    CodeGen::deselect_temporary(gen);
+    CodeGen::select_temporary(gen, obj);
+    Vanilla::node(gen, operands[1]);
+    CodeGen::deselect_temporary(gen);
+    CodeGen::select_temporary(gen, p);
+    Vanilla::node(gen, operands[2]);
+    CodeGen::deselect_temporary(gen);
+
+    WRITE("if (%S == OBJECT_TY) {\n", K);
+    WRITE("    if (%S-->0 == 2) {\n", p);
+    WRITE("        if (%S has %S-->1) rtrue; rfalse;\n", obj, p);
+    WRITE("    }\n");
+    WRITE("    if (%S == door_to) return (%S-->1).%S();\n", p, obj, p);
+    WRITE("    return %S.(%S-->1);\n", obj, p);
+    WRITE("} else {\n");
+    WRITE("    holder = value_property_holders-->%S;\n", K);
+    WRITE("    return (holder.(%S-->1))-->(%S+COL_HSIZE);\n", p, obj);
+    WRITE("}\n");
+
+    DISCARD_TEXT(K)
+    DISCARD_TEXT(obj)
+    DISCARD_TEXT(p)
+    return;
+

+
  • This code is used in §9.

+
§9.3.  Invoke special write_gprop9.3 =
+

+
+
+    TEMPORARY_TEXT(K)
+    TEMPORARY_TEXT(obj)
+    TEMPORARY_TEXT(p)
+    TEMPORARY_TEXT(val)
+    CodeGen::select_temporary(gen, K);
+    Vanilla::node(gen, operands[0]);
+    CodeGen::deselect_temporary(gen);
+    CodeGen::select_temporary(gen, obj);
+    Vanilla::node(gen, operands[1]);
+    CodeGen::deselect_temporary(gen);
+    CodeGen::select_temporary(gen, p);
+    Vanilla::node(gen, operands[2]);
+    CodeGen::deselect_temporary(gen);
+    CodeGen::select_temporary(gen, val);
+    Vanilla::node(gen, operands[3]);
+    CodeGen::deselect_temporary(gen);
+
+    WRITE("if (%S == OBJECT_TY) {\n", K);
+    WRITE("    if (%S-->0 == 2) {\n", p);
+    WRITE("        if (%S) give %S %S-->1; else give %S ~(%S-->1);\n", val, obj, p, obj, p);
+    WRITE("    } else {\n");
+    WRITE("        %S.(%S-->1) = %S;\n", obj, p, val);
+    WRITE("    }\n");
+    WRITE("} else {\n");
+    WRITE("    ((value_property_holders-->%S).(%S-->1))-->(%S+COL_HSIZE) = %S;\n", K, p, obj, val);
+    WRITE("}\n");
+
+    DISCARD_TEXT(K)
+    DISCARD_TEXT(obj)
+    DISCARD_TEXT(p)
+    DISCARD_TEXT(val)
+    return;
+

+
  • This code is used in §9.

+
§10.  

+
+
 int I6Target::begin_array(code_generator *cgt, code_generation *gen, text_stream *array_name, inter_symbol *array_s, inter_tree_node *P, int format, segmentation_pos *saved) {
     if (saved) {
         int choice = early_matter_I7CGS;
@@ -1466,7 +1595,7 @@ or implement assembly-language operations like                     else if (aliased == verb_directive_creature_symbol) WRITE("creature");
                     else if (aliased == verb_directive_topic_symbol) WRITE("topic");
                     else if (aliased == verb_directive_multiexcept_symbol) WRITE("multiexcept");
-                    else I6Target::compile_literal_symbol(cgt, gen, aliased);
+                    else I6Target::compile_literal_symbol(cgt, gen, aliased);
                 }
             } else {
                 CodeGen::pair(gen, P, val1, val2);
@@ -1496,7 +1625,7 @@ or implement assembly-language operations like     Generators::mangle(gen, OUT, S);
 }
 

-
§10.  Alternatively, we can just specify how many entries there will be: they will
+
§11.  Alternatively, we can just specify how many entries there will be: they will
 then be initialised to 0.
 

 
diff --git a/docs/runtime-module/5-prp.html b/docs/runtime-module/5-prp.html
index 7b9f1bbce..07a025326 100644
--- a/docs/runtime-module/5-prp.html
+++ b/docs/runtime-module/5-prp.html
@@ -126,7 +126,7 @@ package already supplied:
     return prn->compilation_data.prop_package;
 }
 
-inter_name *RTProperties::iname(property *prn) {
+inter_name *RTProperties::iname(property *prn) {
     if (prn == NULL) internal_error("tried to find iname for null property");
     if ((Properties::is_either_or(prn)) && (prn->compilation_data.store_in_negation))
         return RTProperties::iname(EitherOrProperties::get_negation(prn));
@@ -188,7 +188,7 @@ kit, we'll have to use that one.
 

 
 
-int RTProperties::stored_in_negation(property *prn) {
+int RTProperties::stored_in_negation(property *prn) {
     if ((prn == NULL) || (prn->either_or_data == NULL))
         internal_error("non-EO property");
     return prn->compilation_data.store_in_negation;
@@ -367,89 +367,46 @@ and its analogue for writing,     return TRUE;
 }
 

-
§10.  Either-or properties are trickier, though only because they use a different
-pair of functions at runtime for EO properties of objects than for EO properties
-of anything else:
+
§10.  Either-or properties work analogously, though note that on reading, GProperty
+is called slightly differently so that objects are allowed access to read (though
+not write) either/or properties which they do not possess. The result is always
+false, but run-time errors do not occur. (This all goes back to the way
+attributes were handled on the Z-machine VM, but is an assumption made by some
+of the kit code inherited from early days of Inform, and does no actual harm.)
 

 
 
 void RTProperties::write_either_or_schemas(adjective_meaning *am, property *prn, int T) {
     kind *K = AdjectiveMeaningDomains::get_kind(am);
-    if (Kinds::Behaviour::is_object(K))
-        Set the schemata for an either/or property adjective with objects as domain10.1
-    else
-        Set the schemata for an either/or property adjective with some other domain10.2;
+    if (RTProperties::stored_in_negation(prn)) {
+        property *neg = EitherOrProperties::get_negation(prn);
+
+        i6_schema *sch = AdjectiveMeanings::make_schema(am, TEST_ATOM_TASK);
+        Calculus::Schemas::modify(sch, "GProperty(%k, *1, %n, 1) == false", K,
+            RTProperties::iname(neg));
+
+        sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_TRUE_TASK);
+        Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n, 0)", K,
+            RTProperties::iname(neg));
+
+        sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_FALSE_TASK);
+        Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n, 1)", K,
+            RTProperties::iname(neg));
+    } else {
+        i6_schema *sch = AdjectiveMeanings::make_schema(am, TEST_ATOM_TASK);
+        Calculus::Schemas::modify(sch, "GProperty(%k, *1, %n, 1)", K,
+            RTProperties::iname(prn));
+
+        sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_TRUE_TASK);
+        Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n, 1)", K,
+            RTProperties::iname(prn));
+
+        sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_FALSE_TASK);
+        Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n, 0)", K,
+            RTProperties::iname(prn));
+    }
 }
 

-
§10.1.  The "objects" domain is not really very different, but it's the one used
-overwhelmingly most often, so we will call the relevant routines directly rather
-than accessing them via the unifying routines GProperty and WriteGProperty —
-which would work just as well, but more slowly.
-

-
-
Set the schemata for an either/or property adjective with objects as domain10.1 =
-

-
-
-    if (RTProperties::stored_in_negation(prn)) {
-        property *neg = EitherOrProperties::get_negation(prn);
-        inter_name *identifier = RTProperties::iname(neg);
-
-        i6_schema *sch = AdjectiveMeanings::make_schema(am, TEST_ATOM_TASK);
-        Calculus::Schemas::modify(sch, "GProperty(OBJECT_TY, *1, %n, true) == false", identifier);
-
-        sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_TRUE_TASK);
-        Calculus::Schemas::modify(sch, "WriteGProperty(OBJECT_TY, *1, %n, 0)", identifier);
-
-        sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_FALSE_TASK);
-        Calculus::Schemas::modify(sch, "WriteGProperty(OBJECT_TY, *1, %n, 1)", identifier);
-    } else {
-        inter_name *identifier = RTProperties::iname(prn);
-
-        i6_schema *sch = AdjectiveMeanings::make_schema(am, TEST_ATOM_TASK);
-        Calculus::Schemas::modify(sch, "GProperty(OBJECT_TY, *1, %n, true)", identifier);
-
-        sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_TRUE_TASK);
-        Calculus::Schemas::modify(sch, "WriteGProperty(OBJECT_TY, *1, %n, 1)", identifier);
-
-        sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_FALSE_TASK);
-        Calculus::Schemas::modify(sch, "WriteGProperty(OBJECT_TY, *1, %n, 0)", identifier);
-    }
-

-
  • This code is used in §10.

-
§10.2.  Set the schemata for an either/or property adjective with some other domain10.2 =
-

-
-
-    if (RTProperties::stored_in_negation(prn)) {
-        property *neg = EitherOrProperties::get_negation(prn);
-
-        i6_schema *sch = AdjectiveMeanings::make_schema(am, TEST_ATOM_TASK);
-        Calculus::Schemas::modify(sch, "GProperty(%k, *1, %n) == false", K,
-            RTProperties::iname(neg));
-
-        sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_TRUE_TASK);
-        Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n)", K,
-            RTProperties::iname(neg));
-
-        sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_FALSE_TASK);
-        Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n, true)", K,
-            RTProperties::iname(neg));
-    } else {
-        i6_schema *sch = AdjectiveMeanings::make_schema(am, TEST_ATOM_TASK);
-        Calculus::Schemas::modify(sch, "GProperty(%k, *1, %n)", K,
-            RTProperties::iname(prn));
-
-        sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_TRUE_TASK);
-        Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n, true)", K,
-            RTProperties::iname(prn));
-
-        sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_FALSE_TASK);
-        Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n)", K,
-            RTProperties::iname(prn));
-    }
-

-
  • This code is used in §10.

 
§11.  And finally, provision of a property can be tested at runtime with the
 following schemas:
 

@@ -468,7 +425,7 @@ following schemas:
         } else if (Kinds::Behaviour::is_object(K)) {
             kind *PK = Cinders::kind_of_term(asch->pt1);
             if (Kinds::get_construct(PK) == CON_property) {
-                Calculus::Schemas::modify(asch->schema, "WhetherProvides(%k, *1, *2)", K);
+                Calculus::Schemas::modify(asch->schema, "ProvidesProperty(%k, *1, *2)", K);
                 return TRUE;
             }
         }
@@ -484,7 +441,7 @@ of object the left operand is, we can only test property provision at run-time:
 

 
 
-    Calculus::Schemas::modify(asch->schema, "WhetherProvides(%k, *1, *2)", K);
+    Calculus::Schemas::modify(asch->schema, "ProvidesProperty(%k, *1, *2)", K);
 

 
  • This code is used in §11.

 
§11.2.  For all other kinds, type-checking is strong enough that we can prove the
diff --git a/inform7/Figures/memory-diagnostics.txt b/inform7/Figures/memory-diagnostics.txt
index 5d558d79e..1d785b107 100644
--- a/inform7/Figures/memory-diagnostics.txt
+++ b/inform7/Figures/memory-diagnostics.txt
@@ -1,6 +1,6 @@
-Total memory consumption was 394323K = 385 MB
+Total memory consumption was 394317K = 385 MB
 
-60.6% was used for 2004452 objects, in 372321 frames in 299 x 800K = 239200K = 233 MB:
+60.6% was used for 2004468 objects, in 372337 frames in 299 x 800K = 239200K = 233 MB:
 
     10.3%  inter_tree_node_array                    58 x 8192 = 475136 objects, 41813824 bytes
      7.2%  text_stream_array                        5187 x 100 = 518700 objects, 29213184 bytes
@@ -13,7 +13,7 @@ Total memory consumption was 394323K = 385 MB
      0.8%  inter_name_array                         69 x 1000 = 69000 objects, 3314208 bytes
      0.6%  kind_array                               68 x 1000 = 68000 objects, 2722176 bytes
      0.5%  inter_name_generator_array               53 x 1000 = 53000 objects, 2121696 bytes
-     0.5%  inter_schema_token                       14185 objects, 2042640 bytes
+     0.5%  inter_schema_token                       14197 objects, 2044368 bytes
      0.4%  inter_package                            26565 objects, 1912680 bytes
      0.4%  package_request                          21137 objects, 1860056 bytes
      0.4%  vocabulary_entry_array                   161 x 100 = 16100 objects, 1808352 bytes
@@ -30,7 +30,7 @@ Total memory consumption was 394323K = 385 MB
      0.2%  ptoken                                   8382 objects, 871728 bytes
      0.2%  grammatical_usage                        3611 objects, 866640 bytes
      0.2%  individual_form                          2561 objects, 860496 bytes
-     0.2%  inter_schema_node                        8905 objects, 854880 bytes
+     0.2%  inter_schema_node                        8909 objects, 855264 bytes
      0.1%  unary_predicate_array                    16 x 1000 = 16000 objects, 640512 bytes
      0.1%  local_variable_array                     47 x 100 = 4700 objects, 452704 bytes
      ----  scan_directory                           94 objects, 388032 bytes
@@ -238,7 +238,7 @@ Total memory consumption was 394323K = 385 MB
 
 39.3% was used for memory not allocated for objects:
 
-    20.5%  text stream storage                      82882584 bytes in 536688 claims
+    20.5%  text stream storage                      82876796 bytes in 536689 claims
      4.5%  dictionary storage                       18271744 bytes in 33265 claims
      ----  sorting                                  736 bytes in 3 claims
      1.7%  source text                              7200000 bytes in 3 claims
@@ -246,8 +246,8 @@ Total memory consumption was 394323K = 385 MB
      ----  documentation fragments                  262144 bytes in 1 claim
      ----  linguistic stock array                   81920 bytes in 2 claims
      ----  small word set array                     105600 bytes in 22 claims
-     1.0%  inter symbols storage                    4175072 bytes in 27677 claims
-     4.1%  inter bytecode storage                   16802732 bytes in 14 claims
+     1.0%  inter symbols storage                    4174576 bytes in 27676 claims
+     4.1%  inter bytecode storage                   16802744 bytes in 14 claims
      4.0%  inter links storage                      16174208 bytes in 266 claims
      ----  inter tree location list storage         191232 bytes in 32 claims
      0.4%  instance-of-kind counting                1695204 bytes in 1 claim
@@ -256,5 +256,5 @@ Total memory consumption was 394323K = 385 MB
      ----  code generation workspace for objects    4128 bytes in 4 claims
      ----  emitter array storage                    161792 bytes in 2062 claims
 
-18.4% was overhead - 74415928 bytes = 72671K = 70 MB
+18.4% was overhead - 74413816 bytes = 72669K = 70 MB
 
diff --git a/inform7/Figures/timings-diagnostics.txt b/inform7/Figures/timings-diagnostics.txt
index 2d1f7c083..9e28d97e5 100644
--- a/inform7/Figures/timings-diagnostics.txt
+++ b/inform7/Figures/timings-diagnostics.txt
@@ -1,11 +1,11 @@
 100.0% in inform7 run
-     55.0% in compilation to Inter
-         39.5% in //Sequence::undertake_queued_tasks//
+     55.1% in compilation to Inter
+         39.6% in //Sequence::undertake_queued_tasks//
           3.5% in //MajorNodes::pre_pass//
-          2.6% in //MajorNodes::pass_1//
-          2.1% in //RTPhrasebook::compile_entries//
-          1.4% in //ImperativeDefinitions::assess_all//
-          1.1% in //RTKindConstructors::compile//
+          2.5% in //MajorNodes::pass_1//
+          2.0% in //RTPhrasebook::compile_entries//
+          1.3% in //ImperativeDefinitions::assess_all//
+          1.2% in //RTKindConstructors::compile//
           0.4% in //ImperativeDefinitions::compile_first_block//
           0.4% in //MajorNodes::pass_2//
           0.4% in //Sequence::undertake_queued_tasks//
@@ -16,22 +16,22 @@
           0.1% in //RTKindConstructors::compile_permissions//
           0.1% in //Task::make_built_in_kind_constructors//
           0.1% in //World::stages_II_and_III//
-          1.6% not specifically accounted for
-     43.1% in running Inter pipeline
-         12.4% in step preparation
+          1.8% not specifically accounted for
+     42.9% in running Inter pipeline
+         12.5% in step preparation
           9.6% in inter step 7/16: consolidate-text
-          7.8% in inter step 2/16: link
-          6.8% in inter step 16/16: generate inform6 -> auto.inf
+          8.0% in inter step 2/16: link
+          6.5% in inter step 16/16: generate inform6 -> auto.inf
           1.5% in inter step 11/16: make-identifiers-unique
           0.4% in inter step 12/16: reconcile-verbs
+          0.2% in inter step 10/16: detect-indirect-calls
           0.2% in inter step 14/16: eliminate-redundant-operations
           0.2% in inter step 6/16: assimilate
           0.2% in inter step 8/16: resolve-external-symbols
           0.2% in inter step 9/16: inspect-plugs
-          0.1% in inter step 10/16: detect-indirect-calls
           0.1% in inter step 13/16: eliminate-redundant-labels
           0.1% in inter step 4/16: parse-linked-matter
           0.1% in inter step 5/16: resolve-conditional-compilation
-          2.7% not specifically accounted for
-      1.7% in supervisor
-      0.2% not specifically accounted for
+          2.4% not specifically accounted for
+      1.6% in supervisor
+      0.3% not specifically accounted for
diff --git a/inform7/Internal/Inter/BasicInformKit/Sections/RTP.i6t b/inform7/Internal/Inter/BasicInformKit/Sections/RTP.i6t
index cc3006401..7f62a107c 100644
--- a/inform7/Internal/Inter/BasicInformKit/Sections/RTP.i6t
+++ b/inform7/Internal/Inter/BasicInformKit/Sections/RTP.i6t
@@ -260,41 +260,40 @@ have the property in question at an I6 level -- having permission to have
 it doesn't mean it actually does have.
 
 =
-[ WhetherProvides K obj q issue_rtp  a l holder;
-	if (K ~= OBJECT_TY) {
-		if ((obj < 1) || (obj > value_ranges-->K)) {
-			if (issue_rtp) RunTimeProblem(RTP_BADVALUEPROPERTY);
-			rfalse;
-		} else {
-			holder = value_property_holders-->K;
-			if ((holder) && (holder provides q)) rtrue;
+[ ProvidesProperty K obj q issue_rtp  a l holder;
+	if (K == OBJECT_TY) {
+		if (ScanPropertyMetadata(obj, q, 4)) jump PermissionFound;
+		if (obj provides KD_Count) {
+			l = obj.KD_Count;
+			while (l > 0) {
+				a = l*2;
+				if (ScanPropertyMetadata(KindHierarchy-->a, q, 4)) jump PermissionFound;
+				l = KindHierarchy-->(a+1);
+			}
 		}
-	}
-	if (obj == 0) {
-		if (issue_rtp) RunTimeProblem(RTP_PROPOFNOTHING, 0, q);
+		if (ScanPropertyMetadata(K0_kind, q, 4)) jump PermissionFound;
+		if (issue_rtp) RunTimeProblem(RTP_UNPROVIDED, obj, q);
 		rfalse;
 	}
-	if (metaclass(obj) ~= Object) rfalse;
-	if (q<0) q = ~q;
-
-	if (ScanPropertyMetadata(obj, q, 4)) jump PermissionFound;
-	if (obj provides KD_Count) {
-		l = obj.KD_Count;
-		while (l > 0) {
-			a = l*2;
-			if (ScanPropertyMetadata(KindHierarchy-->a, q, 4)) jump PermissionFound;
-			l = KindHierarchy-->(a+1);
-		}
-	}
-	if (ScanPropertyMetadata(K0_kind, q, 4)) jump PermissionFound;
-	if (issue_rtp) RunTimeProblem(RTP_UNPROVIDED, obj, q);
-	rfalse;
 
 	.PermissionFound;
-		if (q-->2) rtrue;
-		if (obj provides q) rtrue;
-		if (issue_rtp) RunTimeProblem(RTP_UNSET, obj, q);
-		rfalse;
+
+	@provides_gprop K obj q a;
+	if (a) rtrue;
+!	if (K ~= OBJECT_TY) {
+!		if ((obj >= 1) && (obj <= value_ranges-->K)) {
+!			holder = value_property_holders-->K;
+!			if ((holder) && (holder provides q)) rtrue;
+!		}
+!	} else {
+!		if ((obj) && (metaclass(obj) == Object)) {
+!			if (q-->0 == 2) rtrue;
+!			if (obj provides q) rtrue;
+!		}
+!	}
+
+	if (issue_rtp) RunTimeProblem(RTP_UNSET, obj, q);
+	rfalse;
 ];
 
 [ PrintPropertyName  p  textual;
@@ -331,18 +330,20 @@ this enables it to be an I6 routine returning the other side of the door from
 the one which the player is on.
 
 =
-[ GProperty K V pr err holder;
-	if (WhetherProvides(K, V, pr, 1-err)) {
-		if (K == OBJECT_TY) {
-			if (pr-->0 == 2) {
-				if (V has pr) rtrue; rfalse;
-			}
-			if (pr == door_to) return V.pr();
-			return V.pr;
-		} else {
-			holder = value_property_holders-->K;
-			return (holder.pr)-->(V+COL_HSIZE);
-		}
+[ GProperty K V pr err holder val;
+	if (ProvidesProperty(K, V, pr, 1-err)) {
+		@read_gprop K V pr val;
+		return val;
+!		if (K == OBJECT_TY) {
+!			if (pr-->0 == 2) {
+!				if (V has pr) rtrue; rfalse;
+!			}
+!			if (pr == door_to) return V.pr();
+!			return V.pr;
+!		} else {
+!			holder = value_property_holders-->K;
+!			return (holder.pr)-->(V+COL_HSIZE);
+!		}
 	}
 	return 0;
 ];
@@ -354,17 +355,18 @@ converted from an rvalue to an lvalue.
 
 =
 [ WriteGProperty K V pr val holder;
-	if (WhetherProvides(K, V, pr, true)) {
-		if (K == OBJECT_TY) {
-			if (pr-->0 == 2) {
-				if (val) give V pr; else give V ~pr;
-			} else {
-				V.pr = val;
-			}
-		} else {
-			holder = value_property_holders-->K;
-			(holder.pr)-->(V+COL_HSIZE) = val;
-		}
+	if (ProvidesProperty(K, V, pr, true)) {
+		@write_gprop K V pr val;
+!		if (K == OBJECT_TY) {
+!			if (pr-->0 == 2) {
+!				if (val) give V pr; else give V ~pr;
+!			} else {
+!				V.pr = val;
+!			}
+!		} else {
+!			holder = value_property_holders-->K;
+!			(holder.pr)-->(V+COL_HSIZE) = val;
+!		}
 	}
 ];
 
diff --git a/inform7/Tests/Test Makes/Eg4-C/textual.txt b/inform7/Tests/Test Makes/Eg4-C/textual.txt
index 087ecd41f..8d1ecdf79 100644
--- a/inform7/Tests/Test Makes/Eg4-C/textual.txt	
+++ b/inform7/Tests/Test Makes/Eg4-C/textual.txt	
@@ -6545,9 +6545,9 @@ package main _plain
 		symbol public misc #dictionary_table
 		symbol public misc #grammar_table
 		symbol public misc __assembly_sp `sp`
+		symbol public misc KindHierarchy
 		symbol public misc value_ranges
 		symbol public misc value_property_holders
-		symbol public misc KindHierarchy
 		constant String K_unchecked = 0 __veneer=1
 		constant Routine K_unchecked = 0 __veneer=1
 		constant self K_unchecked = 0 __veneer=1
@@ -6558,9 +6558,9 @@ package main _plain
 		constant #dictionary_table K_unchecked = 0 __veneer=1
 		constant #grammar_table K_unchecked = 0 __veneer=1
 		constant __assembly_sp K_unchecked = 0 __veneer=1
+		constant KindHierarchy K_unchecked = 0 __veneer=1
 		constant value_ranges K_unchecked = 0 __veneer=1
 		constant value_property_holders K_unchecked = 0 __veneer=1
-		constant KindHierarchy K_unchecked = 0 __veneer=1
 	package basic_inform_by_graham_nelson _module
 		symbol private misc ^category `^category_U1`
 		symbol external misc K_typeless_int --> /main/generic/kinds/K_typeless_int
@@ -39392,11 +39392,9 @@ package main _plain
 		symbol socket misc RunTimeError --> /main/connectors/RunTimeError
 		symbol socket misc ArgumentTypeFailed --> /main/connectors/ArgumentTypeFailed
 		symbol socket misc CheckKindReturned --> /main/connectors/CheckKindReturned
-		symbol socket misc WhetherProvides --> /main/connectors/WhetherProvides
+		symbol socket misc ProvidesProperty --> /main/connectors/ProvidesProperty
 		symbol socket misc PrintPropertyName --> /main/connectors/PrintPropertyName
 		symbol socket misc ScanPropertyMetadata --> /main/connectors/ScanPropertyMetadata
-		symbol socket misc GetEitherOrProperty --> /main/connectors/GetEitherOrProperty
-		symbol socket misc SetEitherOrProperty --> /main/connectors/SetEitherOrProperty
 		symbol socket misc GProperty --> /main/connectors/GProperty
 		symbol socket misc WriteGProperty --> /main/connectors/WriteGProperty
 		symbol socket misc PROPERTY_TY_Say --> /main/connectors/PROPERTY_TY_Say
@@ -97061,10 +97059,10 @@ package main _plain
 						inv !return
 							val K_unchecked V
 				constant CheckKindReturned K_unchecked_function = CheckKindReturned_B __assimilated=1
-			package WhetherProvides_fn _function
-				symbol public misc WhetherProvides
+			package ProvidesProperty_fn _function
+				symbol public misc ProvidesProperty
 				symbol external misc K_unchecked_function --> /main/generic/kinds/K_unchecked_function
-				package WhetherProvides_B _code
+				package ProvidesProperty_B _code
 					symbol private misc K
 					symbol external misc K_unchecked --> /main/generic/kinds/K_unchecked
 					symbol private misc obj
@@ -97074,19 +97072,17 @@ package main _plain
 					symbol private misc l
 					symbol private misc holder
 					symbol external misc plug_00140 --> /main/generic/kinds/kind1/OBJECT_TY
-					symbol external misc value_ranges --> /main/veneer/value_ranges
-					symbol external misc RunTimeProblem --> /main/BasicInformKit/functions/RunTimeProblem_fn/RunTimeProblem
-					symbol external misc RTP_BADVALUEPROPERTY --> /main/BasicInformKit/constants/RTP_BADVALUEPROPERTY_con/RTP_BADVALUEPROPERTY
-					symbol external misc value_property_holders --> /main/veneer/value_property_holders
-					symbol external misc RTP_PROPOFNOTHING --> /main/BasicInformKit/constants/RTP_PROPOFNOTHING_con/RTP_PROPOFNOTHING
-					symbol external misc metaclass --> /main/veneer/metaclass
-					symbol external misc Object --> /main/veneer/Object
 					symbol external misc ScanPropertyMetadata --> /main/BasicInformKit/functions/ScanPropertyMetadata_fn/ScanPropertyMetadata
 					symbol private label .PermissionFound
 					symbol external misc KD_Count --> /main/BasicInformKit/properties/KD_Count_prop/KD_Count
 					symbol external misc KindHierarchy --> /main/veneer/KindHierarchy
 					symbol external misc plug_00165 --> /main/generic/kinds/kind1/K_object
+					symbol external misc RunTimeProblem --> /main/BasicInformKit/functions/RunTimeProblem_fn/RunTimeProblem
 					symbol external misc RTP_UNPROVIDED --> /main/BasicInformKit/constants/RTP_UNPROVIDED_con/RTP_UNPROVIDED
+					symbol external misc value_ranges --> /main/veneer/value_ranges
+					symbol external misc value_property_holders --> /main/veneer/value_property_holders
+					symbol external misc metaclass --> /main/veneer/metaclass
+					symbol external misc Object --> /main/veneer/Object
 					symbol external misc RTP_UNSET --> /main/BasicInformKit/constants/RTP_UNSET_con/RTP_UNSET
 					local K K_unchecked
 					local obj K_unchecked
@@ -97097,26 +97093,91 @@ package main _plain
 					local holder K_unchecked
 					code
 						inv !if
+							inv !eq
+								val K_unchecked K
+								val K_unchecked OBJECT_TY
+							code
+								inv !if
+									inv ScanPropertyMetadata
+										val K_unchecked obj
+										val K_unchecked q
+										val K_unchecked 4
+									code
+										inv !jump
+											lab .PermissionFound
+								inv !if
+									inv !provides
+										val K_unchecked obj
+										val K_unchecked KD_Count
+									code
+										inv !store
+											reference
+												val K_unchecked l
+											inv !propertyvalue
+												val K_unchecked obj
+												val K_unchecked KD_Count
+										inv !while
+											inv !gt
+												val K_unchecked l
+												val K_unchecked 0
+											code
+												inv !store
+													reference
+														val K_unchecked a
+													inv !times
+														val K_unchecked l
+														val K_unchecked 2
+												inv !if
+													inv ScanPropertyMetadata
+														inv !lookup
+															val K_unchecked KindHierarchy
+															val K_unchecked a
+														val K_unchecked q
+														val K_unchecked 4
+													code
+														inv !jump
+															lab .PermissionFound
+												inv !store
+													reference
+														val K_unchecked l
+													inv !lookup
+														val K_unchecked KindHierarchy
+														inv !plus
+															val K_unchecked a
+															val K_unchecked 1
+								inv !if
+									inv ScanPropertyMetadata
+										val K_unchecked K_object
+										val K_unchecked q
+										val K_unchecked 4
+									code
+										inv !jump
+											lab .PermissionFound
+								inv !if
+									val K_unchecked issue_rtp
+									code
+										inv RunTimeProblem
+											val K_unchecked RTP_UNPROVIDED
+											val K_unchecked obj
+											val K_unchecked q
+								inv !return
+									val K_unchecked 0
+						.PermissionFound
+						inv !ifelse
 							inv !ne
 								val K_unchecked K
 								val K_unchecked OBJECT_TY
 							code
-								inv !ifelse
-									inv !or
-										inv !lt
+								inv !if
+									inv !and
+										inv !ge
 											val K_unchecked obj
 											val K_unchecked 1
-										inv !gt
+										inv !le
 											val K_unchecked obj
 											inv !lookup
 												val K_unchecked value_ranges
 												val K_unchecked K
-									code
-										inv !if
-											val K_unchecked issue_rtp
-											code
-												inv RunTimeProblem
-													val K_unchecked RTP_BADVALUEPROPERTY
 									code
 										inv !store
 											reference
@@ -97133,120 +97194,31 @@ package main _plain
 											code
 												inv !return
 													val K_unchecked 1
-								inv !return
-									val K_unchecked 0
-						inv !if
-							inv !eq
-								val K_unchecked obj
-								val K_unchecked 0
 							code
 								inv !if
-									val K_unchecked issue_rtp
-									code
-										inv RunTimeProblem
-											val K_unchecked RTP_PROPOFNOTHING
-											val K_unchecked 0
-											val K_unchecked q
-								inv !return
-									val K_unchecked 0
-						inv !if
-							inv !ne
-								inv metaclass
-									val K_unchecked obj
-								val K_unchecked Object
-							code
-								inv !return
-									val K_unchecked 0
-						inv !if
-							inv !lt
-								val K_unchecked q
-								val K_unchecked 0
-							code
-								inv !store
-									reference
-										val K_unchecked q
-									inv !bitwisenot
-										val K_unchecked q
-						inv !if
-							inv ScanPropertyMetadata
-								val K_unchecked obj
-								val K_unchecked q
-								val K_unchecked 4
-							code
-								inv !jump
-									lab .PermissionFound
-						inv !if
-							inv !provides
-								val K_unchecked obj
-								val K_unchecked KD_Count
-							code
-								inv !store
-									reference
-										val K_unchecked l
-									inv !propertyvalue
+									inv !and
 										val K_unchecked obj
-										val K_unchecked KD_Count
-								inv !while
-									inv !gt
-										val K_unchecked l
-										val K_unchecked 0
+										inv !eq
+											inv metaclass
+												val K_unchecked obj
+											val K_unchecked Object
 									code
-										inv !store
-											reference
-												val K_unchecked a
-											inv !times
-												val K_unchecked l
-												val K_unchecked 2
 										inv !if
-											inv ScanPropertyMetadata
+											inv !eq
 												inv !lookup
-													val K_unchecked KindHierarchy
-													val K_unchecked a
-												val K_unchecked q
-												val K_unchecked 4
+													val K_unchecked q
+													val K_unchecked 0
+												val K_unchecked 2
 											code
-												inv !jump
-													lab .PermissionFound
-										inv !store
-											reference
-												val K_unchecked l
-											inv !lookup
-												val K_unchecked KindHierarchy
-												inv !plus
-													val K_unchecked a
+												inv !return
+													val K_unchecked 1
+										inv !if
+											inv !provides
+												val K_unchecked obj
+												val K_unchecked q
+											code
+												inv !return
 													val K_unchecked 1
-						inv !if
-							inv ScanPropertyMetadata
-								val K_unchecked K_object
-								val K_unchecked q
-								val K_unchecked 4
-							code
-								inv !jump
-									lab .PermissionFound
-						inv !if
-							val K_unchecked issue_rtp
-							code
-								inv RunTimeProblem
-									val K_unchecked RTP_UNPROVIDED
-									val K_unchecked obj
-									val K_unchecked q
-						inv !return
-							val K_unchecked 0
-						.PermissionFound
-						inv !if
-							inv !lookup
-								val K_unchecked q
-								val K_unchecked 2
-							code
-								inv !return
-									val K_unchecked 1
-						inv !if
-							inv !provides
-								val K_unchecked obj
-								val K_unchecked q
-							code
-								inv !return
-									val K_unchecked 1
 						inv !if
 							val K_unchecked issue_rtp
 							code
@@ -97256,7 +97228,7 @@ package main _plain
 									val K_unchecked q
 						inv !return
 							val K_unchecked 0
-				constant WhetherProvides K_unchecked_function = WhetherProvides_B __assimilated=1
+				constant ProvidesProperty K_unchecked_function = ProvidesProperty_B __assimilated=1
 			package PrintPropertyName_fn _function
 				symbol public misc PrintPropertyName
 				symbol external misc K_unchecked_function --> /main/generic/kinds/K_unchecked_function
@@ -97326,56 +97298,6 @@ package main _plain
 						inv !return
 							val K_unchecked 0
 				constant ScanPropertyMetadata K_unchecked_function = ScanPropertyMetadata_B __assimilated=1
-			package GetEitherOrProperty_fn _function
-				symbol public misc GetEitherOrProperty
-				symbol external misc K_unchecked_function --> /main/generic/kinds/K_unchecked_function
-				package GetEitherOrProperty_B _code
-					symbol private misc o
-					symbol external misc K_unchecked --> /main/generic/kinds/K_unchecked
-					symbol private misc p
-					symbol external misc GProperty --> /main/BasicInformKit/functions/GProperty_fn/GProperty
-					symbol external misc plug_00140 --> /main/generic/kinds/kind1/OBJECT_TY
-					local o K_unchecked
-					local p K_unchecked
-					code
-						inv !return
-							inv GProperty
-								val K_unchecked OBJECT_TY
-								val K_unchecked o
-								val K_unchecked p
-								val K_unchecked 1
-				constant GetEitherOrProperty K_unchecked_function = GetEitherOrProperty_B __assimilated=1
-			package SetEitherOrProperty_fn _function
-				symbol public misc SetEitherOrProperty
-				symbol external misc K_unchecked_function --> /main/generic/kinds/K_unchecked_function
-				package SetEitherOrProperty_B _code
-					symbol private misc o
-					symbol external misc K_unchecked --> /main/generic/kinds/K_unchecked
-					symbol private misc p
-					symbol private misc negate
-					symbol private misc adj
-					symbol external misc WriteGProperty --> /main/BasicInformKit/functions/WriteGProperty_fn/WriteGProperty
-					symbol external misc plug_00140 --> /main/generic/kinds/kind1/OBJECT_TY
-					local o K_unchecked
-					local p K_unchecked
-					local negate K_unchecked
-					local adj K_unchecked
-					code
-						inv !ifelse
-							val K_unchecked negate
-							code
-								inv WriteGProperty
-									val K_unchecked OBJECT_TY
-									val K_unchecked o
-									val K_unchecked p
-									val K_unchecked 0
-							code
-								inv WriteGProperty
-									val K_unchecked OBJECT_TY
-									val K_unchecked o
-									val K_unchecked p
-									val K_unchecked 1
-				constant SetEitherOrProperty K_unchecked_function = SetEitherOrProperty_B __assimilated=1
 			package GProperty_fn _function
 				symbol public misc GProperty
 				symbol external misc K_unchecked_function --> /main/generic/kinds/K_unchecked_function
@@ -97386,7 +97308,7 @@ package main _plain
 					symbol private misc pr
 					symbol private misc err
 					symbol private misc holder
-					symbol external misc WhetherProvides --> /main/BasicInformKit/functions/WhetherProvides_fn/WhetherProvides
+					symbol external misc ProvidesProperty --> /main/BasicInformKit/functions/ProvidesProperty_fn/ProvidesProperty
 					symbol external misc plug_00140 --> /main/generic/kinds/kind1/OBJECT_TY
 					symbol external misc door_to --> /main/BasicInformKit/properties/door_to_prop/door_to
 					symbol external misc value_property_holders --> /main/veneer/value_property_holders
@@ -97398,7 +97320,7 @@ package main _plain
 					local holder K_unchecked
 					code
 						inv !if
-							inv WhetherProvides
+							inv ProvidesProperty
 								val K_unchecked K
 								val K_unchecked V
 								val K_unchecked pr
@@ -97468,7 +97390,7 @@ package main _plain
 					symbol private misc pr
 					symbol private misc val
 					symbol private misc holder
-					symbol external misc WhetherProvides --> /main/BasicInformKit/functions/WhetherProvides_fn/WhetherProvides
+					symbol external misc ProvidesProperty --> /main/BasicInformKit/functions/ProvidesProperty_fn/ProvidesProperty
 					symbol external misc plug_00140 --> /main/generic/kinds/kind1/OBJECT_TY
 					symbol external misc value_property_holders --> /main/veneer/value_property_holders
 					symbol external misc COL_HSIZE --> /main/BasicInformKit/constants/COL_HSIZE_con/COL_HSIZE
@@ -97479,7 +97401,7 @@ package main _plain
 					local holder K_unchecked
 					code
 						inv !if
-							inv WhetherProvides
+							inv ProvidesProperty
 								val K_unchecked K
 								val K_unchecked V
 								val K_unchecked pr
diff --git a/inform7/runtime-module/Chapter 5/Properties.w b/inform7/runtime-module/Chapter 5/Properties.w
index 6f4b2035c..757cee925 100644
--- a/inform7/runtime-module/Chapter 5/Properties.w	
+++ b/inform7/runtime-module/Chapter 5/Properties.w	
@@ -268,79 +268,45 @@ int RTProperties::set_property_value_schema(annotated_i6_schema *asch, property
 	return TRUE;
 }
 
-@ Either-or properties are trickier, though only because they use a different
-pair of functions at runtime for EO properties of objects than for EO properties
-of anything else:
+@ Either-or properties work analogously, though note that on reading, |GProperty|
+is called slightly differently so that objects are allowed access to read (though
+not write) either/or properties which they do not possess. The result is always
+|false|, but run-time errors do not occur. (This all goes back to the way
+attributes were handled on the Z-machine VM, but is an assumption made by some
+of the kit code inherited from early days of Inform, and does no actual harm.)
 
 =
 void RTProperties::write_either_or_schemas(adjective_meaning *am, property *prn, int T) {
 	kind *K = AdjectiveMeaningDomains::get_kind(am);
-	if (Kinds::Behaviour::is_object(K))
-		@
-	else
-		@;
+	if (RTProperties::stored_in_negation(prn)) {
+		property *neg = EitherOrProperties::get_negation(prn);
+
+		i6_schema *sch = AdjectiveMeanings::make_schema(am, TEST_ATOM_TASK);
+		Calculus::Schemas::modify(sch, "GProperty(%k, *1, %n, 1) == false", K,
+			RTProperties::iname(neg));
+
+		sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_TRUE_TASK);
+		Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n, 0)", K,
+			RTProperties::iname(neg));
+
+		sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_FALSE_TASK);
+		Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n, 1)", K,
+			RTProperties::iname(neg));
+	} else {
+		i6_schema *sch = AdjectiveMeanings::make_schema(am, TEST_ATOM_TASK);
+		Calculus::Schemas::modify(sch, "GProperty(%k, *1, %n, 1)", K,
+			RTProperties::iname(prn));
+
+		sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_TRUE_TASK);
+		Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n, 1)", K,
+			RTProperties::iname(prn));
+
+		sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_FALSE_TASK);
+		Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n, 0)", K,
+			RTProperties::iname(prn));
+	}
 }
 
-@ The "objects" domain is not really very different, but it's the one used
-overwhelmingly most often, so we will call the relevant routines directly rather
-than accessing them via the unifying routines |GProperty| and |WriteGProperty| --
-which would work just as well, but more slowly.
-
-@ =
-	if (RTProperties::stored_in_negation(prn)) {
-		property *neg = EitherOrProperties::get_negation(prn);
-		inter_name *identifier = RTProperties::iname(neg);
-
-		i6_schema *sch = AdjectiveMeanings::make_schema(am, TEST_ATOM_TASK);
-		Calculus::Schemas::modify(sch, "GProperty(OBJECT_TY, *1, %n, true) == false", identifier);
-
-		sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_TRUE_TASK);
-		Calculus::Schemas::modify(sch, "WriteGProperty(OBJECT_TY, *1, %n, 0)", identifier);
-
-		sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_FALSE_TASK);
-		Calculus::Schemas::modify(sch, "WriteGProperty(OBJECT_TY, *1, %n, 1)", identifier);
-	} else {
-		inter_name *identifier = RTProperties::iname(prn);
-
-		i6_schema *sch = AdjectiveMeanings::make_schema(am, TEST_ATOM_TASK);
-		Calculus::Schemas::modify(sch, "GProperty(OBJECT_TY, *1, %n, true)", identifier);
-
-		sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_TRUE_TASK);
-		Calculus::Schemas::modify(sch, "WriteGProperty(OBJECT_TY, *1, %n, 1)", identifier);
-
-		sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_FALSE_TASK);
-		Calculus::Schemas::modify(sch, "WriteGProperty(OBJECT_TY, *1, %n, 0)", identifier);
-	}
-
-@ =
-	if (RTProperties::stored_in_negation(prn)) {
-		property *neg = EitherOrProperties::get_negation(prn);
-
-		i6_schema *sch = AdjectiveMeanings::make_schema(am, TEST_ATOM_TASK);
-		Calculus::Schemas::modify(sch, "GProperty(%k, *1, %n) == false", K,
-			RTProperties::iname(neg));
-
-		sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_TRUE_TASK);
-		Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n)", K,
-			RTProperties::iname(neg));
-
-		sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_FALSE_TASK);
-		Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n, true)", K,
-			RTProperties::iname(neg));
-	} else {
-		i6_schema *sch = AdjectiveMeanings::make_schema(am, TEST_ATOM_TASK);
-		Calculus::Schemas::modify(sch, "GProperty(%k, *1, %n)", K,
-			RTProperties::iname(prn));
-
-		sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_TRUE_TASK);
-		Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n, true)", K,
-			RTProperties::iname(prn));
-
-		sch = AdjectiveMeanings::make_schema(am, NOW_ATOM_FALSE_TASK);
-		Calculus::Schemas::modify(sch, "WriteGProperty(%k, *1, %n)", K,
-			RTProperties::iname(prn));
-	}
-
 @ And finally, provision of a property can be tested at runtime with the
 following schemas:
 
@@ -358,7 +324,7 @@ int RTProperties::test_provision_schema(annotated_i6_schema *asch) {
 		} else if (Kinds::Behaviour::is_object(K)) {
 			kind *PK = Cinders::kind_of_term(asch->pt1);
 			if (Kinds::get_construct(PK) == CON_property) {
-				Calculus::Schemas::modify(asch->schema, "WhetherProvides(%k, *1, *2)", K);
+				Calculus::Schemas::modify(asch->schema, "ProvidesProperty(%k, *1, *2)", K);
 				return TRUE;
 			}
 		}
@@ -370,7 +336,7 @@ int RTProperties::test_provision_schema(annotated_i6_schema *asch) {
 of object the left operand is, we can only test property provision at run-time:
 
 @ =
-	Calculus::Schemas::modify(asch->schema, "WhetherProvides(%k, *1, *2)", K);
+	Calculus::Schemas::modify(asch->schema, "ProvidesProperty(%k, *1, *2)", K);
 
 @ For all other kinds, type-checking is strong enough that we can prove the
 answer now.
diff --git a/inter/final-module/Chapter 4/Final Inform 6.w b/inter/final-module/Chapter 4/Final Inform 6.w
index 34c91b845..89dd1c085 100644
--- a/inter/final-module/Chapter 4/Final Inform 6.w	
+++ b/inter/final-module/Chapter 4/Final Inform 6.w	
@@ -1219,6 +1219,9 @@ void I6Target::invoke_opcode(code_generator *cgt, code_generation *gen,
 	text_stream *opcode, int operand_count, inter_tree_node **operands,
 	inter_tree_node *label, int label_sense, int void_context) {
 	text_stream *OUT = CodeGen::current(gen);
+	if (Str::eq(opcode, I"@provides_gprop")) @;
+	if (Str::eq(opcode, I"@read_gprop")) @;
+	if (Str::eq(opcode, I"@write_gprop")) @;
 	WRITE("%S", opcode);
 	for (int opc = 0; opc < operand_count; opc++) {
 		WRITE(" ");
@@ -1232,6 +1235,118 @@ void I6Target::invoke_opcode(code_generator *cgt, code_generation *gen,
 	if (void_context) WRITE(";\n");
 }
 
+@ =
+	TEMPORARY_TEXT(K)
+	TEMPORARY_TEXT(obj)
+	TEMPORARY_TEXT(p)
+	TEMPORARY_TEXT(val)
+	CodeGen::select_temporary(gen, K);
+	Vanilla::node(gen, operands[0]);
+	CodeGen::deselect_temporary(gen);
+	CodeGen::select_temporary(gen, obj);
+	Vanilla::node(gen, operands[1]);
+	CodeGen::deselect_temporary(gen);
+	CodeGen::select_temporary(gen, p);
+	Vanilla::node(gen, operands[2]);
+	CodeGen::deselect_temporary(gen);
+	CodeGen::select_temporary(gen, val);
+	Vanilla::node(gen, operands[3]);
+	CodeGen::deselect_temporary(gen);
+
+	WRITE("if (%S == OBJECT_TY) {\n", K);
+	WRITE("    if ((%S) && (metaclass(%S) == Object)) {\n", obj, obj);
+	WRITE("        if ((%S-->0 == 2) || (%S provides %S-->1)) {\n", p, obj, p);
+	WRITE("            %S = 1;\n", val);
+	WRITE("        } else {\n");
+	WRITE("            %S = 0;\n", val);
+	WRITE("        }\n");
+	WRITE("    } else {\n");
+	WRITE("        %S = 0;\n", val);
+	WRITE("    }\n");
+	WRITE("} else {\n");
+	WRITE("    if ((%S >= 1) && (%S <= value_ranges-->%S)) {\n", obj, obj, K);
+	WRITE("        holder = value_property_holders-->%S;\n", K);
+	WRITE("        if ((holder) && (holder provides %S-->1)) {\n", p);
+	WRITE("            %S = 1;\n", val);
+	WRITE("        } else {\n");
+	WRITE("            %S = 0;\n", val);
+	WRITE("        }\n");
+	WRITE("    } else {\n");
+	WRITE("        %S = 0;\n", val);
+	WRITE("    }\n");
+	WRITE("}\n");
+
+	DISCARD_TEXT(K)
+	DISCARD_TEXT(obj)
+	DISCARD_TEXT(p)
+	DISCARD_TEXT(val)
+	return;
+
+@ =
+	TEMPORARY_TEXT(K)
+	TEMPORARY_TEXT(obj)
+	TEMPORARY_TEXT(p)
+	CodeGen::select_temporary(gen, K);
+	Vanilla::node(gen, operands[0]);
+	CodeGen::deselect_temporary(gen);
+	CodeGen::select_temporary(gen, obj);
+	Vanilla::node(gen, operands[1]);
+	CodeGen::deselect_temporary(gen);
+	CodeGen::select_temporary(gen, p);
+	Vanilla::node(gen, operands[2]);
+	CodeGen::deselect_temporary(gen);
+
+	WRITE("if (%S == OBJECT_TY) {\n", K);
+	WRITE("    if (%S-->0 == 2) {\n", p);
+	WRITE("        if (%S has %S-->1) rtrue; rfalse;\n", obj, p);
+	WRITE("    }\n");
+	WRITE("    if (%S == door_to) return (%S-->1).%S();\n", p, obj, p);
+	WRITE("    return %S.(%S-->1);\n", obj, p);
+	WRITE("} else {\n");
+	WRITE("    holder = value_property_holders-->%S;\n", K);
+	WRITE("    return (holder.(%S-->1))-->(%S+COL_HSIZE);\n", p, obj);
+	WRITE("}\n");
+
+	DISCARD_TEXT(K)
+	DISCARD_TEXT(obj)
+	DISCARD_TEXT(p)
+	return;
+
+@ =
+	TEMPORARY_TEXT(K)
+	TEMPORARY_TEXT(obj)
+	TEMPORARY_TEXT(p)
+	TEMPORARY_TEXT(val)
+	CodeGen::select_temporary(gen, K);
+	Vanilla::node(gen, operands[0]);
+	CodeGen::deselect_temporary(gen);
+	CodeGen::select_temporary(gen, obj);
+	Vanilla::node(gen, operands[1]);
+	CodeGen::deselect_temporary(gen);
+	CodeGen::select_temporary(gen, p);
+	Vanilla::node(gen, operands[2]);
+	CodeGen::deselect_temporary(gen);
+	CodeGen::select_temporary(gen, val);
+	Vanilla::node(gen, operands[3]);
+	CodeGen::deselect_temporary(gen);
+
+	WRITE("if (%S == OBJECT_TY) {\n", K);
+	WRITE("    if (%S-->0 == 2) {\n", p);
+	WRITE("        if (%S) give %S %S-->1; else give %S ~(%S-->1);\n", val, obj, p, obj, p);
+	WRITE("    } else {\n");
+	WRITE("        %S.(%S-->1) = %S;\n", obj, p, val);
+	WRITE("    }\n");
+	WRITE("} else {\n");
+	WRITE("    ((value_property_holders-->%S).(%S-->1))-->(%S+COL_HSIZE) = %S;\n", K, p, obj, val);
+	WRITE("}\n");
+
+	DISCARD_TEXT(K)
+	DISCARD_TEXT(obj)
+	DISCARD_TEXT(p)
+	DISCARD_TEXT(val)
+	return;
+
+@ =
 int I6Target::begin_array(code_generator *cgt, code_generation *gen, text_stream *array_name, inter_symbol *array_s, inter_tree_node *P, int format, segmentation_pos *saved) {
 	if (saved) {
 		int choice = early_matter_I7CGS;