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authorCliff Click <cliffc@acm.org>2024-08-06 13:09:38 +0100
committerCliff Click <cliffc@acm.org>2026-10-04 13:30:41 -0700
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Chapter 14: Numeric Types
Co-authored-by: Thalia Archibald <thalia@archibald.dev> Co-authored-by: Tamás Hadházy <85063808+Hels15@users.noreply.github.com> Co-authored-by: Hsiang-Ying Fu <66062782+fuhsnn@users.noreply.github.com> Co-authored-by: Dibyendu Majumdar <mobile@majumdar.org.uk> Co-authored-by: tannal <tannal2409@gmail.com> Co-authored-by: hadha <helsgithub15@gmail.com> Co-authored-by: fuhsnn <66062782+fuhsnn@users.noreply.github.com> Co-authored-by: XmiliaH <45106915+XmiliaH@users.noreply.github.com> Co-authored-by: RobertObkircher <robert.obkircher@gmail.com> Co-authored-by: Robert Obkircher <robert.obkircher@gmail.com>
Diffstat (limited to 'docs')
-rw-r--r--docs/chapter14/14-grammar.md122
-rw-r--r--docs/chapter14/Makefile12
-rw-r--r--docs/chapter14/README.md408
-rw-r--r--docs/chapter14/lattice.gv178
-rw-r--r--docs/chapter14/lattice.svg827
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diff --git a/docs/chapter14/14-grammar.md b/docs/chapter14/14-grammar.md
new file mode 100644
index 00000000..f23f81cd
--- /dev/null
+++ b/docs/chapter14/14-grammar.md
@@ -0,0 +1,122 @@
+# Grammar for Chapter 14
+
+```antlrv4
+grammar SimpleLanguage;
+
+program : block EOF ;
+
+block : statement+ ;
+
+
+statement
+ : '{' block '}'
+ | returnStatement
+ | ifStatement
+ | whileStatement
+ | breakStatement
+ | continueStatement
+ | structDeclaration
+ | expressionStatement
+ ;
+
+
+returnStatement : 'return' expression ';' ;
+
+ifStatement : 'if' '(' expression ')' statement ('else' statement)? ;
+
+whileStatement : 'while' '(' expression ')' statement ;
+
+breakStatement : 'break' ';' ;
+
+continueStatement : 'continue' ';' ;
+
+
+structDeclaration : 'struct' IDENTIFIER '{' fields '}' ;
+
+fields : field+ ;
+
+field : type IDENTIFIER ';' ;
+
+
+expressionStatement
+ : type IDENTIFIER ';'
+ | type IDENTIFIER '=' expression ';'
+ | IDENTIFIER '=' expression ';'
+ | expression
+ ;
+
+PRIMTYPE
+ : 'int'
+ | 'i8'
+ | 'i16'
+ | 'i32'
+ | 'i64'
+ | 'u8'
+ | 'u16'
+ | 'u32'
+ | 'flt'
+ | 'f32'
+ | 'f64'
+ | 'bool'
+ ;
+
+type
+ : PRIMTYPE
+ | typeName ('?')?
+ ;
+
+typeName : IDENTIFIER ;
+
+
+expression : bitWiseExpression ;
+
+bitWiseExpression
+ : comparisonExpression ( '&' | '|' | '^' ) comparisonExpression)*
+ ;
+
+comparisonExpression
+ : shiftExpression (('==' | '!='| '>'| '<'| '>='| '<=') shiftExpression)*
+ ;
+
+shiftExpression
+ : additiveExpression ( '<<' | '>>>' | '>>' ) additiveExpression)*
+ ;
+
+additiveExpression
+ : multiplicativeExpression (('+' | '-') multiplicativeExpression)*
+ ;
+
+multiplicativeExpression
+ : unaryExpression (('*' | '/') unaryExpression)*
+ ;
+
+unaryExpression
+ : ('-') unaryExpression
+ | '!' unaryExpression
+ | primaryExpression postFix*
+ ;
+
+primaryExpression
+ : INTEGER_LITERAL
+ | '(' expression ')'
+ | 'true'
+ | 'false'
+ | 'null'
+ | newExpression
+ | IDENTIFIER
+ ;
+
+newExpression : 'new' IDENTIFIER ;
+
+postFix : '.' IDENTIFIER [ '=' expression ] ;
+
+INTEGER_LITERAL
+ : [1-9]DIGIT*
+ | [0]
+ ;
+
+IDENTIFIER : NON_DIGIT (NON_DIGIT | DIGIT)* ;
+
+NON_DIGIT: [a-zA-Z_];
+DIGIT: [0-9];
+```
diff --git a/docs/chapter14/Makefile b/docs/chapter14/Makefile
new file mode 100644
index 00000000..12659b8f
--- /dev/null
+++ b/docs/chapter14/Makefile
@@ -0,0 +1,12 @@
+GV := $(wildcard *.gv)
+SVG := $(patsubst %.gv,%.svg,$(GV))
+
+.PHONY: all
+all: $(SVG)
+
+%.svg: %.gv
+ dot -Tsvg $< > $@
+
+.PHONY: clean
+clean:
+ @rm -f $(SVG)
diff --git a/docs/chapter14/README.md b/docs/chapter14/README.md
new file mode 100644
index 00000000..33374243
--- /dev/null
+++ b/docs/chapter14/README.md
@@ -0,0 +1,408 @@
+# Chapter 14: Numeric Types
+
+[Previous: Chapter 13](../chapter13/README.md) |
+[Next: Chapter 15](../chapter15/README.md)
+
+# Table of Contents
+
+1. [Floating-point arithmetic](#floating-point-arithmetic)
+2. [Narrow Word Types](#narrow-or-sub-word-types)
+3. [Overflow handling](#overflow-handling)
+4. [Integer ranges](#integer-ranges)
+5. [Bitwise operations](#bitwise-operations)
+6. [Precedence](#precedence)
+7. [Type lattice](#type-implementation)
+8. [Nodes](#nodes)
+
+
+With structs, reference fields, and scheduling in place, this chapter extends
+the numeric values they carry. We add floating-point arithmetic, narrow
+integer and float types, and integer ranges.
+
+You can also read [this chapter](https://github.com/SeaOfNodes/Simple/tree/linear-chapter14) in a linear Git revision history on the [linear](https://github.com/SeaOfNodes/Simple/tree/linear) branch and [compare](https://github.com/SeaOfNodes/Simple/compare/linear-chapter13...linear-chapter14) it to the previous chapter.
+
+## Floating-point arithmetic
+
+Floating point values start with the `flt` type and compute IEEE754 64-bit arithmetic.
+Integer expressions auto-widen to floats when involved in a float expression.
+
+```java
+flt f = 0.5;
+int x = 2;
+f = f+x; // Auto-widen x to 2.0, result is 2.5
+f = f+true; // Since bools are just synonyms for integers 0,1 they auto-widen also
+```
+
+There is no corresponding way right now to round a `flt` back to an `int`:
+```java
+int x = 3.14; // error
+```
+
+Here is Newton's method for computing a square root:
+```java
+flt guess = arg; // Initial guess is just argument
+while( true ) {
+ // Next guess from Newton's method
+ flt next = (arg/guess + guess)/2;
+ // Break if hit fixed point
+ if( next == guess ) break;
+ guess = next;
+}
+return guess;
+```
+When run with argument 2, produces 1.414213562373095.
+
+Floating point operations have their own Nodes:
+
+| Node | Op |
+|------------------------|----------------------|
+| AddF, SubF, MulF, DivF | Basic binary FP ops |
+| MinusF | Unary negate |
+| EQF, LTF, LEF | FP compare operators |
+
+The parser uses [`Node.widen()`](../../src/main/java/com/seaofnodes/simple/node/Node.java)
+to choose the floating-point operation and insert `ToFloatNode` conversions.
+The float lattice has constants between `TOP` and `BOT`, like the integer
+lattice before ranges. [`TypeFloat`](../../src/main/java/com/seaofnodes/simple/type/TypeFloat.java)
+also records whether a value fits `f32`; assigning to `f32` rounds it to that
+precision. Conversion from float back to integer remains a separate, pending
+language feature.
+
+
+## Narrow or sub-word types
+
+Narrow or sub-word integer types refer to integer data types that occupy less
+memory (fewer bits) than the standard or "full-width" (typically 32 or 64 bits)
+integer types provided by a system or programming language.
+
+As a prelude to arrays, especially arrays of bytes common in all networking
+codes, Simple needs some way to manipulate sub-word integer types.
+Computations are always done in 64 bits for both integer and float ops, but
+will be truncated (rounded) on a variable or field assignment, and (sign)
+extended on a load.
+
+```java
+i8 x = 123456789;
+if( x != 21 )
+ return false;
+return true;
+```
+
+The variable `x` is limited to 8 bits signed. Assigning the very large value
+`123456789` (hex `0x75BCD15`) simply truncates to 8 bits yielding `21 (0x15)`.
+The value is sign-extended on a load.
+
+```java
+i16 x = 123456789;
+if( x != -13035 )
+ return false;
+return true;
+```
+
+The variable `x` is limited to 16 bits signed. Assigning the very large value
+`0x75BCD15` simply truncates to 16 bits yielding `0xCD15`. The value is
+sign-extended on a load yielding `-13035 (0xFFFF FFFF FFFF CD15)`.
+
+```java
+u16 x = 123456789;
+if( x != 52501 )
+ return false;
+return true;
+```
+
+The variable `x` is limited to 16 bits unsigned. Assigning the very large value
+`0x75BCD15` simply truncates to 16 bits yielding `0xCD15`. The value is
+zero-extended on a load yielding `52501 (0x0000 0000 0000 CD15)`.
+
+Similarly, floats can be limited to IEEE754 32-bit standard format and will be
+rounded when assigned, and inflated to 64-bits when loaded.
+
+The complete list of primitive types is now:
+
+| Data Type | Size (Bits) | Description |
+|-----------|-------------|--------------------------------------------------------------|
+| `int`, `i64` | 64 | 64-bit signed integer, matching modern hardware. |
+| `u64` | 64 | **Not implemented**, hints at behavior beyond 64-bit. |
+| `i32` | 32 | 32-bit signed integer, sign-extended on load. |
+| `u32` | 32 | 32-bit unsigned integer, zero-extended on load. |
+| `i16` | 16 | 16-bit signed integer, sign-extended on load. |
+| `u16` | 16 | 16-bit unsigned integer, zero-extended on load. |
+| `i8` | 8 | 8-bit signed integer, sign-extended on load. |
+| `u8` | 8 | 8-bit unsigned integer, zero-extended on load. |
+| `i1` | 1 | 1-bit signed integer, sign-extended on load. |
+| `u1` | 1 | 1-bit unsigned integer, zero-extended on load. |
+| `bool` | 1 | Alias for `u1`. |
+| `flt`, `f64`| 64 | IEEE 754 64-bit floating-point number, often called a double. |
+| `f32` | 32 | IEEE 754 32-bit floating-point number. |
+
+## Overflow handling
+
+An integer overflow occurs when you attempt to store inside an integer variable a value that is larger than the maximum value the variable can hold.
+There are several cases of overflow:
+
+#### Unsigned(fixed-width) integer overflow:
+
+```java
+u8 a = 255;
+u8 b = a + 1; // match u8 type against expr.type
+// a = 256
+// u8 = [0...255]
+return b;
+```
+The expression type does not match the type that was provided. expr: ConstantNode(256) t: u8(0, 255)
+```java
+private Node parseExpressionStatement() {
+ Type t = type(); // u8 = [0...255]
+ ...
+ // expr.type = TypeInteger(256);
+ // Auto-narrow wide ints to narrow ints
+ expr = zsMask(expr,t);
+}
+```
+Since it is unsigned we just do a bitmask on the new value that overflows the specified type:
+The operands to the "bitwise AND" are the values(256) and the mask(255, max boundary).
+This is called truncating.
+
+`ZsMask:`
+```java
+ // zero/sign extend. "i" is limited to either classic unsigned (min==0) or
+ // classic signed (min=minus-power-of-2); max=power-of-2-minus-1.
+private Node zsMask(Node val, Type t ) {
+ if( !(val._type instanceof TypeInteger tval && t instanceof TypeInteger t0 && !tval.isa(t0)) ) {
+ if( !(val._type instanceof TypeFloat tval && t instanceof TypeFloat t0 && !tval.isa(t0)) )
+ return val;
+ // Float rounding
+ return new RoundF32Node(val).peephole();
+ }
+ if( t0._min==0 ) // Unsigned
+ return new AndNode(val,new ConstantNode(TypeInteger.constant(t0._max)).peephole()).peephole();
+ // Signed extension
+ int shift = Long.numberOfLeadingZeros(t0._max)-1;
+ Node shf = new ConstantNode(TypeInteger.constant(shift)).peephole();
+ if( shf._type==TypeInteger.ZERO )
+ return val;
+ return new SarNode(new ShlNode(val,shf.keep()).peephole(),shf.unkeep()).peephole();
+}
+```
+
+The truncation is done by the `AndNode`:
+```java
+...
+if( t0._min==0 ) // Unsigned
+ return new AndNode(val,con(t0._max)).peephole();
+```
+Since they are constants, after calling peephole it turns into `256 & 255` = 0;
+Output:
+```
+return 0;
+```
+
+#### Maximum integer overflow
+```java
+i64 a = 9223372036854775807;
+i64 b = a + 1;
+return b;
+```
+When we are computing the addition, we make sure they don't overflow:
+
+`AddNode.overflow:`
+```java
+private static boolean overflow( long x, long y ) {
+ if( (x ^ y ) < 0 ) return false; // unequal signs, never overflow
+ return (x ^ (x + y)) < 0; // sum has unequal signs, so overflow
+}
+```
+`AddNode.compute`
+```java
+...
+// Fold ranges like {0-1} + {2-3} into {2-4}.
+if( !overflow(i1._min,i2._min) &&
+ !overflow(i1._max,i2._max) )
+ return TypeInteger.make(i1._min+i2._min,i1._max+i2._max);
+```
+Here **x + y** overflows and becomes **negative**, x ^ negative = negative. Any negative number is less than 0, so it returns true.
+If it **overflows** we just return the bottom type of TypeInteger.
+```
+ return TypeInteger.BOT; // []
+```
+However, in our case we are dealing with constants, so we just allow the overflow naturally here:
+```java
+// i1: 9223372036854775807
+// i2: 1
+// i1 + i2 will overflow.
+return TypeInteger.constant(i1.value()+i2.value()); // -9223372036854775808;
+```
+
+#### Adding constant ranges
+```java
+u8 a = 12;
+u8 b = 13;
+u8 c = 124;
+u8 d = a + b + c;
+return d;
+```
+if `is_con` is true, then generally we can state: `min = max`.
+Such that:
+```java
+public static TypeInteger make(boolean is_con, long con) {
+ return make(is_con ? con : (con==0 ? Long.MAX_VALUE : Long.MIN_VALUE),
+ is_con ? con : (con==0 ? Long.MIN_VALUE : Long.MAX_VALUE));
+```
+- This results in:
+```java
+return make(con, con);
+```
+
+`value()` is only called in constants, e.g `_min == _max;` invariant holds, then since
+both `min_` and `max_` are equal, we can return either one.
+
+This is the same as regular additions:
+```java
+public long value() { assert isConstant(); return _min; }
+```
+
+#### More Truncate
+
+```java
+u8 a = arg; // arg & 255
+u8 b = arg; // arg & 255 (same as a)
+u8 c = a + b; // (arg&255)*2, type = TypeInteger.BOT
+return c; // (((arg&255)*2)&255), type = TypeInteger.U8
+```
+
+Same as before, **arg** turns into **(arg&255)**, this node is then inserted into the **GVN** table and **b** retrieves this value.
+The AddNode peephole will change them into `((arg&255)*2)`, and put on extra mask
+on the expression to keep it in the valid boundaries.
+
+
+## Integer ranges
+
+For general range math, visit Hackers Delight:[^1]
+
+## Bitwise operations
+We support the following bitwise operators:
+And `&`, Or `|`, Xor `^`, Shift left `<<`, Shift right `>>`, Shift right zero `>>>`
+
+| Operator | Symbol | Description |
+|--------------------------|---------|---------------------------------------------------------------------------------------------------------|
+| **And** | `&` | Performs a bitwise AND operation. |
+| **Or** | `\|` | Performs a bitwise OR (inclusive OR) operation. |
+| **Xor** | `^` | Performs a bitwise XOR (exclusive OR) operation. |
+| **Shift Left** | `<<` | Shifts bits to the left, filling with zeros. |
+| **Shift Right** | `>>` | Shifts bits to the right, any vacated bit positions are filled by replicating the value of the sign bit. |
+| **Unsigned Right Shift** | `>>>` | Shifts bits to the right, any vacated bit positions are always filled with zero |
+
+Note `>>>` is a logical shift and not an arithmetic shift.
+
+Here is a sample of peephole opts on these logical operations:
+
+#### AndNode:
+
+##### lhs & -1 = lhs;
+```java
+// And of -1. We do not check for (-1&x) because this will already
+// canonicalize to (x&-1)
+if( t2.isConstant() && t2 instanceof TypeInteger i && i.value()==-1 )
+return lhs;
+
+```
+
+#### OrNode:
+##### lhs | 0 = lhs;
+```java
+// Or of 0. We do not check for (0|x) because this will already
+// canonicalize to (x|0)
+if( t2.isConstant() && t2 instanceof TypeInteger i && i.value()==0 )
+return lhs;
+
+```
+
+#### Shift right
+lhs >> 0 = lhs;
+```java
+// Sar of 0.
+if( t2.isConstant() && t2 instanceof TypeInteger i && (i.value()&63)==0 )
+ return lhs;
+```
+
+#### Shift left
+lhs << 0 = lhs;
+```java
+// Shl of 0.
+if( t2.isConstant() && t2 instanceof TypeInteger i && (i.value()&63)==0 )
+ return lhs;
+
+```
+#### Unsigned right shift
+lhs >>> 0 = lhs;
+```java
+// Shr of 0.
+if( t2.isConstant() && t2 instanceof TypeInteger i && (i.value()&63)==0 )
+return lhs;
+```
+
+#### XorNode:
+##### lhs ^ 0 = lhs;
+```java
+// Xor of 0. We do not check for (0^x) because this will already
+// canonicalize to (x^0)
+if( t2.isConstant() && t2 instanceof TypeInteger i && i.value()==0 )
+ return lhs;
+
+```
+### precedence
+
+Bitwise operators have the lowest precedence, e.g
+```
+arg + 123 & 3 = (arg + 123) & 3
+```
+
+## Type Implementation
+
+The ![Integer](../chapter10/type-integer.svg) `TypeInteger` class is
+reworked to support a full range of min/max values. At this time, only some
+power-of-2 sized ranges are exposed to the programmer but the optimizer
+internally supports all ranges. The MEET operation takes the min-of-mins and
+max-of-maxes. The DUAL operation inverts the min and max.
+
+Example: the constant `0` has `[0...0]`.
+
+Example: the `bool` type has the range `[0...1]`.
+
+Example: the `u8` type has the range `[0...255]`.
+
+Example: the `i8` type has the range `[-128...127]`.
+
+Example: the `dual` of `bool` is `[1...0]` (just swap min and max).
+
+The ![Float](../type-float.svg) `TypeFloat` class introduced here supports
+both 32-bit and 64-bit sizes.
+
+The integer range diagram is schematic: it shows the boolean range and its
+dual as examples among the possible ranges. The other domains retain the
+named structs, nullable pointers, and precise memory aliases from earlier chapters.
+
+![Graph1](./lattice.svg)
+
+### meet:
+
+The Meet of two ranges:
+```java
+@Override
+public Type xmeet(Type other) {
+// Invariant from caller: 'this' != 'other' and same class (TypeInteger)
+TypeInteger i = (TypeInteger)other; // Contract
+return make(Math.min(_min,i._min), Math.max(_max,i._max));
+}
+```
+
+This combines all values that could possibly occur within either range.
+Also, the implementation is trivial.
+
+
+
+[^1]: Hacker's delight.
+ 4-2 Propagating Bounds through Adds and Subtracts
+
+The next chapter uses these numeric types for array lengths, indexing, and
+element storage, including byte arrays.
diff --git a/docs/chapter14/lattice.gv b/docs/chapter14/lattice.gv
new file mode 100644
index 00000000..5fd97a52
--- /dev/null
+++ b/docs/chapter14/lattice.gv
@@ -0,0 +1,178 @@
+digraph Lattice {
+ rankdir=TB;
+ newrank=true;
+ // Preserve the same-rank ordering edges through cluster layout.
+ remincross=false;
+ nodesep=0.22;
+ ranksep=0.65;
+ node [shape=ellipse, style=filled, fontname="DejaVu Sans", fontsize=13];
+ edge [color="#555555", arrowsize=0.6];
+
+ // These arrows are lattice-order edges, not use/definition edges.
+ TOP [label="⊤", fillcolor=black, fontcolor=white];
+ BOT [label="⊥", fillcolor=black, fontcolor=white];
+
+ subgraph cluster_control {
+ label="Control"; fontname="Arial"; color="#cccccc";
+ node [fillcolor="#ffff00"];
+ XCTRL [label="⊤:ctrl"];
+ CTRL [label="⊥:ctrl"];
+ XCTRL -> CTRL;
+ }
+
+ subgraph cluster_integer {
+ label="Integer ranges (schematic)"; fontname="Arial"; color="#cccccc";
+ INT_TOP [label=<<B>⊤</B >:int>, fillcolor=lightblue, shape=oval];
+ INT_BOT [label=<<B>⊥</B>:int>, fillcolor=lightblue, shape=oval];
+
+ INT_HI [label="max < min" , fillcolor=lightblue, shape=oval];
+ INT_XBOOL [label="1...0", fillcolor=lightblue, shape=oval];
+ INT_CON [label="constants", fillcolor=lightblue, shape=oval];
+ INT_CON0 [label="0", fillcolor=lightblue];
+ INT_CON1 [label="1", fillcolor=lightblue];
+ INT_BOOL [label="0...1", fillcolor=lightblue,shape=oval];
+ INT_LO [label="max > min" , fillcolor=lightblue, shape=oval];
+
+ INT_TOP -> INT_HI;
+ INT_HI -> INT_XBOOL;
+ INT_XBOOL -> INT_CON0;
+ INT_XBOOL -> INT_CON1;
+ INT_HI -> INT_CON;
+ INT_CON0 -> INT_BOOL;
+ INT_CON1 -> INT_BOOL;
+ INT_BOOL -> INT_LO;
+ INT_CON -> INT_LO;
+ INT_LO -> INT_BOT;
+
+ INT_CON0 -> INT_CON1 -> INT_CON [style=invis];
+
+ {rank=same; INT_CON0; INT_CON1; INT_CON;}
+ }
+
+ subgraph cluster_float {
+ label="Float"; fontname="Arial"; color="#cccccc";
+ FLT_TOP [label=<<B>⊤</B >:flt>, fillcolor=aqua, shape=oval];
+ FLT_BOT [label=<<B>⊥</B>:flt>, fillcolor=aqua, shape=oval];
+
+ FLT_CON64 [label="64b consts\n[excludes\n32b consts]" , fillcolor=aqua, shape=oval];
+ FLT_CON32 [label="32b consts", fillcolor=aqua, shape=oval];
+ FLT_CONPI [label="3.14159...", fillcolor=aqua, shape=oval];
+ FLT_X32 [label="~f32", fillcolor=aqua];
+ FLT_CON0 [label="0." , fillcolor=aqua];
+ FLT_32 [label="f32" , fillcolor=aqua];
+
+ FLT_TOP -> FLT_CON64
+ FLT_TOP -> FLT_CONPI
+ FLT_CON64 -> FLT_BOT
+ FLT_CONPI -> FLT_BOT
+
+ FLT_TOP -> FLT_X32;
+ FLT_X32 -> FLT_CON0;
+ FLT_X32 -> FLT_CON32;
+ FLT_CON0 -> FLT_32;
+ FLT_CON32 -> FLT_32;
+ FLT_32 -> FLT_BOT
+
+ FLT_CON0 -> FLT_CON32 -> FLT_CONPI -> FLT_CON64 [style=invis];
+
+
+ {rank=same; FLT_CON0; FLT_CON32; FLT_CONPI; FLT_CON64;}
+ }
+
+ subgraph cluster_pointer {
+ label="Pointer = nullability × struct type";
+ fontname="Arial"; color="#cccccc";
+ node [fillcolor="#008000", fontcolor=white];
+ PTR_TOP [label="⊤:ptr\n[*⊤:struct]"];
+ PTR_BOT [label="⊥:ptr\n[*⊥:struct?]"];
+ PTR_NULL [label="null"];
+ PTR_ANY [label="*⊥:struct\n[ptr any struct]"];
+ PTR_PERSON [label="*Person"];
+ PTR_S1 [label="*s1"];
+ PTR_MORE [label="*s2, …"];
+ PTR_PERSON_NIL [label="*Person?"];
+ PTR_S1_NIL [label="*s1?"];
+ PTR_MORE_NIL [label="*s2?, …"];
+ {rank=same; PTR_PERSON; PTR_S1; PTR_MORE; PTR_NULL;}
+ {rank=same; PTR_ANY; PTR_PERSON_NIL; PTR_S1_NIL; PTR_MORE_NIL;}
+ PTR_PERSON -> PTR_S1 -> PTR_MORE -> PTR_NULL [style=invis];
+ PTR_ANY -> PTR_PERSON_NIL -> PTR_S1_NIL -> PTR_MORE_NIL [style=invis];
+ PTR_TOP -> {PTR_PERSON PTR_S1 PTR_MORE PTR_NULL};
+ {PTR_PERSON PTR_S1 PTR_MORE} -> PTR_ANY;
+ PTR_PERSON -> PTR_PERSON_NIL;
+ PTR_S1 -> PTR_S1_NIL;
+ PTR_MORE -> PTR_MORE_NIL;
+ PTR_NULL -> {PTR_PERSON_NIL PTR_S1_NIL PTR_MORE_NIL};
+ {PTR_ANY PTR_PERSON_NIL PTR_S1_NIL PTR_MORE_NIL} -> PTR_BOT;
+ }
+
+ subgraph cluster_struct {
+ label="Struct\nnamed collection of named scalar types";
+ fontname="Arial"; color="#cccccc";
+ node [fillcolor="#90ee90"];
+ STRUCT_TOP [label="⊤:struct\n[struct top]"];
+ STRUCT_BOT [label="⊥:struct\n[struct bottom]"];
+ STRUCT_PERSON [label="Person\nage: int", shape=box];
+ STRUCT_S1 [label="s1\nx: int", shape=box];
+ STRUCT_S2 [label="s2\nx: int, y: *s1", shape=box];
+ STRUCT_MORE [label="…", shape=box];
+ {rank=same; STRUCT_PERSON; STRUCT_S1; STRUCT_S2; STRUCT_MORE;}
+ STRUCT_PERSON -> STRUCT_S1 -> STRUCT_S2 -> STRUCT_MORE [style=invis];
+ STRUCT_TOP -> {STRUCT_PERSON STRUCT_S1 STRUCT_S2 STRUCT_MORE};
+ {STRUCT_PERSON STRUCT_S1 STRUCT_S2 STRUCT_MORE} -> STRUCT_BOT;
+ }
+
+ subgraph cluster_memory {
+ label="Memory\nprecise alias slices"; fontname="Arial"; color="#cccccc";
+ node [fillcolor="#00008b", fontcolor=white];
+ MEM_TOP [label="⊤:mem"];
+ MEM_BOT [label="⊥:mem"];
+ MEM_ALIAS2 [label="MEM#2"];
+ MEM_ALIAS3 [label="MEM#3"];
+ MEM_MORE [label="…"];
+ {rank=same; MEM_ALIAS2; MEM_ALIAS3; MEM_MORE;}
+ MEM_ALIAS2 -> MEM_ALIAS3 -> MEM_MORE [style=invis];
+ MEM_TOP -> {MEM_ALIAS2 MEM_ALIAS3 MEM_MORE};
+ {MEM_ALIAS2 MEM_ALIAS3 MEM_MORE} -> MEM_BOT;
+ }
+
+ subgraph cluster_tuple {
+ label="Tuple\ncollection of types";
+ fontname="Arial"; color="#cccccc";
+ node [fillcolor="#ffc0cb"];
+ TUPLE_TOP [label="⊤:tuple"];
+ TUPLE_BOT [label="⊥:tuple"];
+ // Each black element stands for a recursively nested type lattice.
+ TUPLE1 [shape=plain, label=<
+ <TABLE BORDER="0" CELLBORDER="1" CELLSPACING="0" CELLPADDING="4">
+ <TR><TD BGCOLOR="#ffc0cb">tuple</TD></TR>
+ <TR><TD BGCOLOR="black"><FONT COLOR="white">type</FONT></TD></TR>
+ </TABLE>
+ >];
+ TUPLE2 [shape=plain, label=<
+ <TABLE BORDER="0" CELLBORDER="1" CELLSPACING="0" CELLPADDING="4">
+ <TR><TD BGCOLOR="#ffc0cb">tuple</TD></TR>
+ <TR><TD BGCOLOR="black"><FONT COLOR="white">type</FONT></TD></TR>
+ <TR><TD BGCOLOR="black"><FONT COLOR="white">type</FONT></TD></TR>
+ </TABLE>
+ >];
+ TUPLEN [shape=plain, label=<
+ <TABLE BORDER="0" CELLBORDER="1" CELLSPACING="0" CELLPADDING="4">
+ <TR><TD BGCOLOR="#ffc0cb">tuple</TD></TR>
+ <TR><TD BGCOLOR="black"><FONT COLOR="white">type</FONT></TD></TR>
+ <TR><TD BGCOLOR="black"><FONT COLOR="white">…</FONT></TD></TR>
+ <TR><TD BGCOLOR="black"><FONT COLOR="white">type</FONT></TD></TR>
+ </TABLE>
+ >];
+ {rank=same; TUPLE1; TUPLE2; TUPLEN;}
+ TUPLE1 -> TUPLE2 -> TUPLEN [style=invis];
+ TUPLE_TOP -> {TUPLE1 TUPLE2 TUPLEN};
+ {TUPLE1 TUPLE2 TUPLEN} -> TUPLE_BOT;
+ }
+
+ TOP -> {XCTRL INT_TOP FLT_TOP PTR_TOP STRUCT_TOP MEM_TOP TUPLE_TOP};
+ {CTRL INT_BOT FLT_BOT PTR_BOT STRUCT_BOT MEM_BOT TUPLE_BOT} -> BOT;
+ {rank=same; XCTRL; INT_TOP; FLT_TOP; PTR_TOP; STRUCT_TOP; MEM_TOP; TUPLE_TOP;}
+ {rank=same; CTRL; INT_BOT; FLT_BOT; PTR_BOT; STRUCT_BOT; MEM_BOT; TUPLE_BOT;}
+ XCTRL -> INT_TOP -> FLT_TOP -> PTR_TOP -> STRUCT_TOP -> MEM_TOP -> TUPLE_TOP [style=invis];
+}
diff --git a/docs/chapter14/lattice.svg b/docs/chapter14/lattice.svg
new file mode 100644
index 00000000..9db77f7a
--- /dev/null
+++ b/docs/chapter14/lattice.svg
@@ -0,0 +1,827 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
+ "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
+<!-- Generated by graphviz version 12.2.0 (20241103.1931)
+ -->
+<!-- Title: Lattice Pages: 1 -->
+<svg width="2191pt" height="881pt"
+ viewBox="0.00 0.00 2191.00 880.78" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
+<g id="graph0" class="graph" transform="scale(1 1) rotate(0) translate(4 876.78)">
+<title>Lattice</title>
+<polygon fill="white" stroke="none" points="-4,4 -4,-876.78 2187,-876.78 2187,4 -4,4"/>
+<g id="clust1" class="cluster">
+<title>cluster_control</title>
+<polygon fill="none" stroke="#cccccc" points="8,-85.99 8,-802.04 98,-802.04 98,-85.99 8,-85.99"/>
+<text text-anchor="middle" x="53" y="-784.74" font-family="Arial" font-size="14.00">Control</text>
+</g>
+<g id="clust2" class="cluster">
+<title>cluster_integer</title>
+<polygon fill="none" stroke="#cccccc" points="106,-85.99 106,-802.04 372,-802.04 372,-85.99 106,-85.99"/>
+<text text-anchor="middle" x="239" y="-784.74" font-family="Arial" font-size="14.00">Integer ranges (schematic)</text>
+</g>
+<g id="clust4" class="cluster">
+<title>cluster_float</title>
+<polygon fill="none" stroke="#cccccc" points="380,-85.99 380,-802.04 864,-802.04 864,-85.99 380,-85.99"/>
+<text text-anchor="middle" x="622" y="-784.74" font-family="Arial" font-size="14.00">Float</text>
+</g>
+<g id="clust6" class="cluster">
+<title>cluster_pointer</title>
+<polygon fill="none" stroke="#cccccc" points="872,-75 872,-813.03 1353,-813.03 1353,-75 872,-75"/>
+<text text-anchor="middle" x="1112.5" y="-795.73" font-family="Arial" font-size="14.00">Pointer = nullability × struct type</text>
+</g>
+<g id="clust13" class="cluster">
+<title>cluster_struct</title>
+<polygon fill="none" stroke="#cccccc" points="1361,-75 1361,-828.78 1697,-828.78 1697,-75 1361,-75"/>
+<text text-anchor="middle" x="1529" y="-811.48" font-family="Arial" font-size="14.00">Struct</text>
+<text text-anchor="middle" x="1529" y="-795.73" font-family="Arial" font-size="14.00">named collection of named scalar types</text>
+</g>
+<g id="clust17" class="cluster">
+<title>cluster_memory</title>
+<polygon fill="none" stroke="#cccccc" points="1705,-85.99 1705,-817.79 1987,-817.79 1987,-85.99 1705,-85.99"/>
+<text text-anchor="middle" x="1846" y="-800.49" font-family="Arial" font-size="14.00">Memory</text>
+<text text-anchor="middle" x="1846" y="-784.74" font-family="Arial" font-size="14.00">precise alias slices</text>
+</g>
+<g id="clust21" class="cluster">
+<title>cluster_tuple</title>
+<polygon fill="none" stroke="#cccccc" points="1995,-85.99 1995,-817.79 2175,-817.79 2175,-85.99 1995,-85.99"/>
+<text text-anchor="middle" x="2085" y="-800.49" font-family="Arial" font-size="14.00">Tuple</text>
+<text text-anchor="middle" x="2085" y="-784.74" font-family="Arial" font-size="14.00">collection of types</text>
+</g>
+<!-- TOP -->
+<g id="node1" class="node">
+<title>TOP</title>
+<ellipse fill="black" stroke="black" cx="1093" cy="-854.78" rx="27" ry="18"/>
+<text text-anchor="middle" x="1093" y="-850.68" font-family="DejaVu Sans" font-size="13.00" fill="white">⊤</text>
+</g>
+<!-- XCTRL -->
+<g id="node3" class="node">
+<title>XCTRL</title>
+<ellipse fill="#ffff00" stroke="black" cx="53" cy="-752.29" rx="36.51" ry="18"/>
+<text text-anchor="middle" x="53" y="-748.19" font-family="DejaVu Sans" font-size="13.00">⊤:ctrl</text>
+</g>
+<!-- TOP&#45;&gt;XCTRL -->
+<g id="edge77" class="edge">
+<title>TOP&#45;&gt;XCTRL</title>
+<path fill="none" stroke="#555555" d="M1065.75,-853.81C910.7,-853.87 145.18,-852.94 102,-828.78 82.14,-817.67 69.01,-794.76 61.39,-777.08"/>
+<polygon fill="#555555" stroke="#555555" points="63.43,-776.52 59.22,-771.76 59.54,-778.1 63.43,-776.52"/>
+</g>
+<!-- INT_TOP -->
+<g id="node5" class="node">
+<title>INT_TOP</title>
+<ellipse fill="lightblue" stroke="black" cx="330" cy="-752.29" rx="33.95" ry="18"/>
+<text text-anchor="start" x="313.12" y="-749.19" font-family="DejaVu Sans" font-weight="bold" font-size="13.00">⊤</text>
+<text text-anchor="start" x="325.12" y="-749.19" font-family="DejaVu Sans" font-size="13.00">:int</text>
+</g>
+<!-- TOP&#45;&gt;INT_TOP -->
+<g id="edge78" class="edge">
+<title>TOP&#45;&gt;INT_TOP</title>
+<path fill="none" stroke="#555555" d="M1065.76,-853.55C938.37,-852.39 406.27,-846.49 376,-828.78 356.7,-817.5 344.47,-794.61 337.51,-776.98"/>
+<polygon fill="#555555" stroke="#555555" points="339.61,-776.59 335.55,-771.7 335.67,-778.05 339.61,-776.59"/>
+</g>
+<!-- FLT_TOP -->
+<g id="node14" class="node">
+<title>FLT_TOP</title>
+<ellipse fill="aqua" stroke="black" cx="720" cy="-752.29" rx="31.39" ry="18"/>
+<text text-anchor="start" x="705" y="-749.19" font-family="DejaVu Sans" font-weight="bold" font-size="13.00">⊤</text>
+<text text-anchor="start" x="717" y="-749.19" font-family="DejaVu Sans" font-size="13.00">:flt</text>
+</g>
+<!-- TOP&#45;&gt;FLT_TOP -->
+<g id="edge79" class="edge">
+<title>TOP&#45;&gt;FLT_TOP</title>
+<path fill="none" stroke="#555555" d="M1065.71,-853.88C1022.73,-853.35 937.09,-849.49 868,-828.78 822.79,-815.23 774.91,-788.16 746.24,-770.39"/>
+<polygon fill="#555555" stroke="#555555" points="747.56,-768.74 741.36,-767.33 745.33,-772.3 747.56,-768.74"/>
+</g>
+<!-- PTR_TOP -->
+<g id="node22" class="node">
+<title>PTR_TOP</title>
+<ellipse fill="#008000" stroke="black" cx="1093" cy="-752.29" rx="61.7" ry="28.99"/>
+<text text-anchor="middle" x="1093" y="-756.44" font-family="DejaVu Sans" font-size="13.00" fill="white">⊤:ptr</text>
+<text text-anchor="middle" x="1093" y="-739.94" font-family="DejaVu Sans" font-size="13.00" fill="white">[*⊤:struct]</text>
+</g>
+<!-- TOP&#45;&gt;PTR_TOP -->
+<g id="edge80" class="edge">
+<title>TOP&#45;&gt;PTR_TOP</title>
+<path fill="none" stroke="#555555" d="M1093,-836.74C1093,-823.62 1093,-805.05 1093,-788.76"/>
+<polygon fill="#555555" stroke="#555555" points="1095.1,-788.97 1093,-782.97 1090.9,-788.97 1095.1,-788.97"/>
+</g>
+<!-- STRUCT_TOP -->
+<g id="node32" class="node">
+<title>STRUCT_TOP</title>
+<ellipse fill="#90ee90" stroke="black" cx="1480" cy="-752.29" rx="64.35" ry="28.99"/>
+<text text-anchor="middle" x="1480" y="-756.44" font-family="DejaVu Sans" font-size="13.00">⊤:struct</text>
+<text text-anchor="middle" x="1480" y="-739.94" font-family="DejaVu Sans" font-size="13.00">[struct top]</text>
+</g>
+<!-- TOP&#45;&gt;STRUCT_TOP -->
+<g id="edge81" class="edge">
+<title>TOP&#45;&gt;STRUCT_TOP</title>
+<path fill="none" stroke="#555555" d="M1119.97,-852.78C1178.13,-850.35 1313.55,-843.3 1357,-828.78 1388.2,-818.36 1419.74,-798.78 1443.07,-782.17"/>
+<polygon fill="#555555" stroke="#555555" points="1444.26,-783.9 1447.9,-778.68 1441.8,-780.49 1444.26,-783.9"/>
+</g>
+<!-- MEM_TOP -->
+<g id="node38" class="node">
+<title>MEM_TOP</title>
+<ellipse fill="#00008b" stroke="black" cx="1807" cy="-752.29" rx="44.7" ry="18"/>
+<text text-anchor="middle" x="1807" y="-748.19" font-family="DejaVu Sans" font-size="13.00" fill="white">⊤:mem</text>
+</g>
+<!-- TOP&#45;&gt;MEM_TOP -->
+<g id="edge82" class="edge">
+<title>TOP&#45;&gt;MEM_TOP</title>
+<path fill="none" stroke="#555555" d="M1120.14,-853.58C1230.92,-852.61 1645.66,-847.74 1701,-828.78 1734.02,-817.47 1765.78,-792.33 1785.79,-774.16"/>
+<polygon fill="#555555" stroke="#555555" points="1787.02,-775.88 1790,-770.26 1784.17,-772.8 1787.02,-775.88"/>
+</g>
+<!-- TUPLE_TOP -->
+<g id="node43" class="node">
+<title>TUPLE_TOP</title>
+<ellipse fill="#ffc0cb" stroke="black" cx="2048" cy="-752.29" rx="44.7" ry="18"/>
+<text text-anchor="middle" x="2048" y="-748.19" font-family="DejaVu Sans" font-size="13.00">⊤:tuple</text>
+</g>
+<!-- TOP&#45;&gt;TUPLE_TOP -->
+<g id="edge83" class="edge">
+<title>TOP&#45;&gt;TUPLE_TOP</title>
+<path fill="none" stroke="#555555" d="M1120.01,-853.69C1265.56,-853.09 1951.36,-849.22 1991,-828.78 2012.45,-817.73 2028.06,-794.49 2037.46,-776.7"/>
+<polygon fill="#555555" stroke="#555555" points="2039.12,-778.07 2039.96,-771.77 2035.37,-776.17 2039.12,-778.07"/>
+</g>
+<!-- BOT -->
+<g id="node2" class="node">
+<title>BOT</title>
+<ellipse fill="black" stroke="black" cx="1158" cy="-18" rx="27" ry="18"/>
+<text text-anchor="middle" x="1158" y="-13.9" font-family="DejaVu Sans" font-size="13.00" fill="white">⊥</text>
+</g>
+<!-- CTRL -->
+<g id="node4" class="node">
+<title>CTRL</title>
+<ellipse fill="#ffff00" stroke="black" cx="53" cy="-111.99" rx="36.51" ry="18"/>
+<text text-anchor="middle" x="53" y="-107.89" font-family="DejaVu Sans" font-size="13.00">⊥:ctrl</text>
+</g>
+<!-- XCTRL&#45;&gt;CTRL -->
+<g id="edge1" class="edge">
+<title>XCTRL&#45;&gt;CTRL</title>
+<path fill="none" stroke="#555555" d="M53,-733.84C53,-699.39 53,-620.21 53,-553.64 53,-553.64 53,-553.64 53,-292.98 53,-237.49 53,-172.38 53,-137.7"/>
+<polygon fill="#555555" stroke="#555555" points="55.1,-137.88 53,-131.88 50.9,-137.88 55.1,-137.88"/>
+</g>
+<!-- XCTRL&#45;&gt;INT_TOP -->
+<!-- CTRL&#45;&gt;BOT -->
+<g id="edge84" class="edge">
+<title>CTRL&#45;&gt;BOT</title>
+<path fill="none" stroke="#555555" d="M68.82,-95.67C77.79,-87.99 89.68,-79.4 102,-75 199.9,-40.01 951.33,-23.1 1123.11,-19.66"/>
+<polygon fill="#555555" stroke="#555555" points="1123.14,-21.76 1129.1,-19.55 1123.06,-17.57 1123.14,-21.76"/>
+</g>
+<!-- INT_HI -->
+<g id="node7" class="node">
+<title>INT_HI</title>
+<ellipse fill="lightblue" stroke="black" cx="303" cy="-658.3" rx="61.08" ry="18"/>
+<text text-anchor="middle" x="303" y="-654.2" font-family="DejaVu Sans" font-size="13.00">max &lt; min</text>
+</g>
+<!-- INT_TOP&#45;&gt;INT_HI -->
+<g id="edge2" class="edge">
+<title>INT_TOP&#45;&gt;INT_HI</title>
+<path fill="none" stroke="#555555" d="M325.05,-734.42C320.88,-720.2 314.85,-699.69 310.16,-683.69"/>
+<polygon fill="#555555" stroke="#555555" points="312.24,-683.31 308.53,-678.14 308.21,-684.49 312.24,-683.31"/>
+</g>
+<!-- INT_TOP&#45;&gt;FLT_TOP -->
+<!-- INT_BOT -->
+<g id="node6" class="node">
+<title>INT_BOT</title>
+<ellipse fill="lightblue" stroke="black" cx="316" cy="-111.99" rx="33.95" ry="18"/>
+<text text-anchor="start" x="299.12" y="-108.89" font-family="DejaVu Sans" font-weight="bold" font-size="13.00">⊥</text>
+<text text-anchor="start" x="311.12" y="-108.89" font-family="DejaVu Sans" font-size="13.00">:int</text>
+</g>
+<!-- INT_BOT&#45;&gt;BOT -->
+<g id="edge85" class="edge">
+<title>INT_BOT&#45;&gt;BOT</title>
+<path fill="none" stroke="#555555" d="M334.62,-96.69C345.94,-88.82 361.06,-79.72 376,-75 518.37,-30.04 991.01,-21.01 1123.31,-19.35"/>
+<polygon fill="#555555" stroke="#555555" points="1123.32,-21.45 1129.3,-19.28 1123.27,-17.25 1123.32,-21.45"/>
+</g>
+<!-- INT_XBOOL -->
+<g id="node8" class="node">
+<title>INT_XBOOL</title>
+<ellipse fill="lightblue" stroke="black" cx="211" cy="-552.64" rx="31.39" ry="18"/>
+<text text-anchor="middle" x="211" y="-548.54" font-family="DejaVu Sans" font-size="13.00">1...0</text>
+</g>
+<!-- INT_HI&#45;&gt;INT_XBOOL -->
+<g id="edge3" class="edge">
+<title>INT_HI&#45;&gt;INT_XBOOL</title>
+<path fill="none" stroke="#555555" d="M288.22,-640.65C272.25,-622.65 246.77,-593.94 229.48,-574.47"/>
+<polygon fill="#555555" stroke="#555555" points="231.4,-573.46 225.85,-570.37 228.26,-576.25 231.4,-573.46"/>
+</g>
+<!-- INT_CON -->
+<g id="node9" class="node">
+<title>INT_CON</title>
+<ellipse fill="lightblue" stroke="black" cx="309" cy="-411.98" rx="54.93" ry="18"/>
+<text text-anchor="middle" x="309" y="-407.88" font-family="DejaVu Sans" font-size="13.00">constants</text>
+</g>
+<!-- INT_HI&#45;&gt;INT_CON -->
+<g id="edge6" class="edge">
+<title>INT_HI&#45;&gt;INT_CON</title>
+<path fill="none" stroke="#555555" d="M303.42,-640.12C304.47,-597.64 307.17,-487.54 308.39,-437.9"/>
+<polygon fill="#555555" stroke="#555555" points="310.49,-438.03 308.53,-431.98 306.29,-437.93 310.49,-438.03"/>
+</g>
+<!-- INT_CON0 -->
+<g id="node10" class="node">
+<title>INT_CON0</title>
+<ellipse fill="lightblue" stroke="black" cx="141" cy="-411.98" rx="27" ry="18"/>
+<text text-anchor="middle" x="141" y="-407.88" font-family="DejaVu Sans" font-size="13.00">0</text>
+</g>
+<!-- INT_XBOOL&#45;&gt;INT_CON0 -->
+<g id="edge4" class="edge">
+<title>INT_XBOOL&#45;&gt;INT_CON0</title>
+<path fill="none" stroke="#555555" d="M202.56,-534.92C190.09,-510.21 166.7,-463.9 152.62,-436.01"/>
+<polygon fill="#555555" stroke="#555555" points="154.52,-435.1 149.94,-430.69 150.77,-436.99 154.52,-435.1"/>
+</g>
+<!-- INT_CON1 -->
+<g id="node11" class="node">
+<title>INT_CON1</title>
+<ellipse fill="lightblue" stroke="black" cx="211" cy="-411.98" rx="27" ry="18"/>
+<text text-anchor="middle" x="211" y="-407.88" font-family="DejaVu Sans" font-size="13.00">1</text>
+</g>
+<!-- INT_XBOOL&#45;&gt;INT_CON1 -->
+<g id="edge5" class="edge">
+<title>INT_XBOOL&#45;&gt;INT_CON1</title>
+<path fill="none" stroke="#555555" d="M211,-534.36C211,-510.07 211,-465.7 211,-437.86"/>
+<polygon fill="#555555" stroke="#555555" points="213.1,-437.99 211,-431.99 208.9,-437.99 213.1,-437.99"/>
+</g>
+<!-- INT_LO -->
+<g id="node13" class="node">
+<title>INT_LO</title>
+<ellipse fill="lightblue" stroke="black" cx="303" cy="-208.48" rx="61.08" ry="18"/>
+<text text-anchor="middle" x="303" y="-204.38" font-family="DejaVu Sans" font-size="13.00">max &gt; min</text>
+</g>
+<!-- INT_CON&#45;&gt;INT_LO -->
+<g id="edge10" class="edge">
+<title>INT_CON&#45;&gt;INT_LO</title>
+<path fill="none" stroke="#555555" d="M308.49,-393.8C307.43,-358.13 304.98,-275.9 303.74,-234.4"/>
+<polygon fill="#555555" stroke="#555555" points="305.84,-234.35 303.56,-228.42 301.64,-234.48 305.84,-234.35"/>
+</g>
+<!-- INT_CON0&#45;&gt;INT_CON1 -->
+<!-- INT_BOOL -->
+<g id="node12" class="node">
+<title>INT_BOOL</title>
+<ellipse fill="lightblue" stroke="black" cx="211" cy="-293.98" rx="31.39" ry="18"/>
+<text text-anchor="middle" x="211" y="-289.88" font-family="DejaVu Sans" font-size="13.00">0...1</text>
+</g>
+<!-- INT_CON0&#45;&gt;INT_BOOL -->
+<g id="edge7" class="edge">
+<title>INT_CON0&#45;&gt;INT_BOOL</title>
+<path fill="none" stroke="#555555" d="M150.73,-394.85C162.84,-374.8 183.57,-340.43 197.28,-317.71"/>
+<polygon fill="#555555" stroke="#555555" points="199.04,-318.87 200.34,-312.64 195.44,-316.7 199.04,-318.87"/>
+</g>
+<!-- INT_CON1&#45;&gt;INT_CON -->
+<!-- INT_CON1&#45;&gt;INT_BOOL -->
+<g id="edge8" class="edge">
+<title>INT_CON1&#45;&gt;INT_BOOL</title>
+<path fill="none" stroke="#555555" d="M211,-393.62C211,-374.05 211,-342.1 211,-319.88"/>
+<polygon fill="#555555" stroke="#555555" points="213.1,-319.98 211,-313.98 208.9,-319.98 213.1,-319.98"/>
+</g>
+<!-- INT_BOOL&#45;&gt;INT_LO -->
+<g id="edge9" class="edge">
+<title>INT_BOOL&#45;&gt;INT_LO</title>
+<path fill="none" stroke="#555555" d="M227.03,-278.44C241.55,-265.26 263.13,-245.67 279.59,-230.73"/>
+<polygon fill="#555555" stroke="#555555" points="280.8,-232.47 283.83,-226.88 277.98,-229.36 280.8,-232.47"/>
+</g>
+<!-- INT_LO&#45;&gt;INT_BOT -->
+<g id="edge11" class="edge">
+<title>INT_LO&#45;&gt;INT_BOT</title>
+<path fill="none" stroke="#555555" d="M305.38,-190.15C307.42,-175.37 310.37,-153.94 312.64,-137.42"/>
+<polygon fill="#555555" stroke="#555555" points="314.69,-137.94 313.42,-131.71 310.53,-137.37 314.69,-137.94"/>
+</g>
+<!-- FLT_CON64 -->
+<g id="node16" class="node">
+<title>FLT_CON64</title>
+<ellipse fill="aqua" stroke="black" cx="790" cy="-552.64" rx="65.94" ry="40.66"/>
+<text text-anchor="middle" x="790" y="-565.04" font-family="DejaVu Sans" font-size="13.00">64b consts</text>
+<text text-anchor="middle" x="790" y="-548.54" font-family="DejaVu Sans" font-size="13.00">[excludes</text>
+<text text-anchor="middle" x="790" y="-532.04" font-family="DejaVu Sans" font-size="13.00">32b consts]</text>
+</g>
+<!-- FLT_TOP&#45;&gt;FLT_CON64 -->
+<g id="edge14" class="edge">
+<title>FLT_TOP&#45;&gt;FLT_CON64</title>
+<path fill="none" stroke="#555555" d="M725.97,-734.44C736.43,-704.9 758.41,-642.83 773.68,-599.71"/>
+<polygon fill="#555555" stroke="#555555" points="775.64,-600.48 775.66,-594.12 771.68,-599.08 775.64,-600.48"/>
+</g>
+<!-- FLT_CONPI -->
+<g id="node18" class="node">
+<title>FLT_CONPI</title>
+<ellipse fill="aqua" stroke="black" cx="651" cy="-552.64" rx="56.98" ry="18"/>
+<text text-anchor="middle" x="651" y="-548.54" font-family="DejaVu Sans" font-size="13.00">3.14159...</text>
+</g>
+<!-- FLT_TOP&#45;&gt;FLT_CONPI -->
+<g id="edge15" class="edge">
+<title>FLT_TOP&#45;&gt;FLT_CONPI</title>
+<path fill="none" stroke="#555555" d="M714.12,-734.44C701.88,-699.39 673.65,-618.52 659.46,-577.88"/>
+<polygon fill="#555555" stroke="#555555" points="661.52,-577.42 657.56,-572.44 657.56,-578.8 661.52,-577.42"/>
+</g>
+<!-- FLT_X32 -->
+<g id="node19" class="node">
+<title>FLT_X32</title>
+<ellipse fill="aqua" stroke="black" cx="518" cy="-658.3" rx="32.93" ry="18"/>
+<text text-anchor="middle" x="518" y="-654.2" font-family="DejaVu Sans" font-size="13.00">~f32</text>
+</g>
+<!-- FLT_TOP&#45;&gt;FLT_X32 -->
+<g id="edge18" class="edge">
+<title>FLT_TOP&#45;&gt;FLT_X32</title>
+<path fill="none" stroke="#555555" d="M696.03,-740.38C659.58,-723.78 590.16,-692.16 549.62,-673.7"/>
+<polygon fill="#555555" stroke="#555555" points="550.59,-671.83 544.26,-671.26 548.85,-675.66 550.59,-671.83"/>
+</g>
+<!-- FLT_TOP&#45;&gt;PTR_TOP -->
+<!-- FLT_BOT -->
+<g id="node15" class="node">
+<title>FLT_BOT</title>
+<ellipse fill="aqua" stroke="black" cx="720" cy="-111.99" rx="31.39" ry="18"/>
+<text text-anchor="start" x="705" y="-108.89" font-family="DejaVu Sans" font-weight="bold" font-size="13.00">⊥</text>
+<text text-anchor="start" x="717" y="-108.89" font-family="DejaVu Sans" font-size="13.00">:flt</text>
+</g>
+<!-- FLT_BOT&#45;&gt;BOT -->
+<g id="edge86" class="edge">
+<title>FLT_BOT&#45;&gt;BOT</title>
+<path fill="none" stroke="#555555" d="M748.28,-103.69C778,-96.11 826.14,-84.12 868,-75 960.59,-54.81 1070.63,-34.59 1124.67,-24.9"/>
+<polygon fill="#555555" stroke="#555555" points="1124.89,-26.99 1130.43,-23.87 1124.15,-22.86 1124.89,-26.99"/>
+</g>
+<!-- FLT_CON64&#45;&gt;FLT_BOT -->
+<g id="edge16" class="edge">
+<title>FLT_CON64&#45;&gt;FLT_BOT</title>
+<path fill="none" stroke="#555555" d="M783.66,-511.94C769.47,-423.02 735.48,-210 723.92,-137.58"/>
+<polygon fill="#555555" stroke="#555555" points="726.01,-137.32 722.99,-131.73 721.86,-137.98 726.01,-137.32"/>
+</g>
+<!-- FLT_CON32 -->
+<g id="node17" class="node">
+<title>FLT_CON32</title>
+<ellipse fill="aqua" stroke="black" cx="518" cy="-552.64" rx="60.05" ry="18"/>
+<text text-anchor="middle" x="518" y="-548.54" font-family="DejaVu Sans" font-size="13.00">32b consts</text>
+</g>
+<!-- FLT_CON32&#45;&gt;FLT_CONPI -->
+<!-- FLT_32 -->
+<g id="node21" class="node">
+<title>FLT_32</title>
+<ellipse fill="aqua" stroke="black" cx="518" cy="-411.98" rx="27" ry="18"/>
+<text text-anchor="middle" x="518" y="-407.88" font-family="DejaVu Sans" font-size="13.00">f32</text>
+</g>
+<!-- FLT_CON32&#45;&gt;FLT_32 -->
+<g id="edge22" class="edge">
+<title>FLT_CON32&#45;&gt;FLT_32</title>
+<path fill="none" stroke="#555555" d="M518,-534.36C518,-510.07 518,-465.7 518,-437.86"/>
+<polygon fill="#555555" stroke="#555555" points="520.1,-437.99 518,-431.99 515.9,-437.99 520.1,-437.99"/>
+</g>
+<!-- FLT_CONPI&#45;&gt;FLT_BOT -->
+<g id="edge17" class="edge">
+<title>FLT_CONPI&#45;&gt;FLT_BOT</title>
+<path fill="none" stroke="#555555" d="M653.75,-534.18C664.5,-465.79 703.78,-216.13 716.2,-137.13"/>
+<polygon fill="#555555" stroke="#555555" points="718.23,-137.78 717.08,-131.53 714.08,-137.13 718.23,-137.78"/>
+</g>
+<!-- FLT_CONPI&#45;&gt;FLT_CON64 -->
+<!-- FLT_X32&#45;&gt;FLT_CON32 -->
+<g id="edge20" class="edge">
+<title>FLT_X32&#45;&gt;FLT_CON32</title>
+<path fill="none" stroke="#555555" d="M518,-640.18C518,-623.4 518,-597.64 518,-578.58"/>
+<polygon fill="#555555" stroke="#555555" points="520.1,-578.64 518,-572.64 515.9,-578.64 520.1,-578.64"/>
+</g>
+<!-- FLT_CON0 -->
+<g id="node20" class="node">
+<title>FLT_CON0</title>
+<ellipse fill="aqua" stroke="black" cx="415" cy="-552.64" rx="27" ry="18"/>
+<text text-anchor="middle" x="415" y="-548.54" font-family="DejaVu Sans" font-size="13.00">0.</text>
+</g>
+<!-- FLT_X32&#45;&gt;FLT_CON0 -->
+<g id="edge19" class="edge">
+<title>FLT_X32&#45;&gt;FLT_CON0</title>
+<path fill="none" stroke="#555555" d="M501.38,-642.45C487.36,-629.74 466.92,-610.77 450,-593.3 444.13,-587.24 437.97,-580.42 432.47,-574.17"/>
+<polygon fill="#555555" stroke="#555555" points="434.16,-572.91 428.64,-569.77 431,-575.67 434.16,-572.91"/>
+</g>
+<!-- FLT_CON0&#45;&gt;FLT_CON32 -->
+<!-- FLT_CON0&#45;&gt;FLT_32 -->
+<g id="edge21" class="edge">
+<title>FLT_CON0&#45;&gt;FLT_32</title>
+<path fill="none" stroke="#555555" d="M426.62,-536.01C445.1,-511.12 481.26,-462.44 502.13,-434.35"/>
+<polygon fill="#555555" stroke="#555555" points="503.79,-435.63 505.68,-429.57 500.42,-433.13 503.79,-435.63"/>
+</g>
+<!-- FLT_32&#45;&gt;FLT_BOT -->
+<g id="edge23" class="edge">
+<title>FLT_32&#45;&gt;FLT_BOT</title>
+<path fill="none" stroke="#555555" d="M528.58,-395.38C562.1,-345.93 666.07,-192.55 705.04,-135.05"/>
+<polygon fill="#555555" stroke="#555555" points="706.56,-136.56 708.19,-130.41 703.08,-134.2 706.56,-136.56"/>
+</g>
+<!-- PTR_NULL -->
+<g id="node24" class="node">
+<title>PTR_NULL</title>
+<ellipse fill="#008000" stroke="black" cx="1219" cy="-658.3" rx="27.3" ry="18"/>
+<text text-anchor="middle" x="1219" y="-654.2" font-family="DejaVu Sans" font-size="13.00" fill="white">null</text>
+</g>
+<!-- PTR_TOP&#45;&gt;PTR_NULL -->
+<g id="edge33" class="edge">
+<title>PTR_TOP&#45;&gt;PTR_NULL</title>
+<path fill="none" stroke="#555555" d="M1125.78,-727.36C1147.49,-711.51 1175.48,-691.07 1195.1,-676.75"/>
+<polygon fill="#555555" stroke="#555555" points="1196.33,-678.45 1199.93,-673.22 1193.85,-675.06 1196.33,-678.45"/>
+</g>
+<!-- PTR_PERSON -->
+<g id="node26" class="node">
+<title>PTR_PERSON</title>
+<ellipse fill="#008000" stroke="black" cx="962" cy="-658.3" rx="45.72" ry="18"/>
+<text text-anchor="middle" x="962" y="-654.2" font-family="DejaVu Sans" font-size="13.00" fill="white">*Person</text>
+</g>
+<!-- PTR_TOP&#45;&gt;PTR_PERSON -->
+<g id="edge34" class="edge">
+<title>PTR_TOP&#45;&gt;PTR_PERSON</title>
+<path fill="none" stroke="#555555" d="M1059.26,-727.6C1037.69,-712.45 1010.05,-693.04 989.76,-678.79"/>
+<polygon fill="#555555" stroke="#555555" points="991.06,-677.14 984.95,-675.41 988.65,-680.58 991.06,-677.14"/>
+</g>
+<!-- PTR_S1 -->
+<g id="node27" class="node">
+<title>PTR_S1</title>
+<ellipse fill="#008000" stroke="black" cx="1051" cy="-658.3" rx="27" ry="18"/>
+<text text-anchor="middle" x="1051" y="-654.2" font-family="DejaVu Sans" font-size="13.00" fill="white">*s1</text>
+</g>
+<!-- PTR_TOP&#45;&gt;PTR_S1 -->
+<g id="edge35" class="edge">
+<title>PTR_TOP&#45;&gt;PTR_S1</title>
+<path fill="none" stroke="#555555" d="M1080.4,-723.69C1074.4,-710.56 1067.32,-695.04 1061.6,-682.53"/>
+<polygon fill="#555555" stroke="#555555" points="1063.62,-681.88 1059.22,-677.29 1059.8,-683.62 1063.62,-681.88"/>
+</g>
+<!-- PTR_MORE -->
+<g id="node28" class="node">
+<title>PTR_MORE</title>
+<ellipse fill="#008000" stroke="black" cx="1135" cy="-658.3" rx="40.6" ry="18"/>
+<text text-anchor="middle" x="1135" y="-654.2" font-family="DejaVu Sans" font-size="13.00" fill="white">*s2, …</text>
+</g>
+<!-- PTR_TOP&#45;&gt;PTR_MORE -->
+<g id="edge36" class="edge">
+<title>PTR_TOP&#45;&gt;PTR_MORE</title>
+<path fill="none" stroke="#555555" d="M1105.6,-723.69C1111.55,-710.65 1118.59,-695.25 1124.28,-682.78"/>
+<polygon fill="#555555" stroke="#555555" points="1126.08,-683.9 1126.66,-677.57 1122.26,-682.15 1126.08,-683.9"/>
+</g>
+<!-- PTR_TOP&#45;&gt;STRUCT_TOP -->
+<!-- PTR_BOT -->
+<g id="node23" class="node">
+<title>PTR_BOT</title>
+<ellipse fill="#008000" stroke="black" cx="1158" cy="-111.99" rx="66.47" ry="28.99"/>
+<text text-anchor="middle" x="1158" y="-116.14" font-family="DejaVu Sans" font-size="13.00" fill="white">⊥:ptr</text>
+<text text-anchor="middle" x="1158" y="-99.64" font-family="DejaVu Sans" font-size="13.00" fill="white">[*⊥:struct?]</text>
+</g>
+<!-- PTR_BOT&#45;&gt;BOT -->
+<g id="edge87" class="edge">
+<title>PTR_BOT&#45;&gt;BOT</title>
+<path fill="none" stroke="#555555" d="M1158,-82.64C1158,-70.25 1158,-55.86 1158,-43.89"/>
+<polygon fill="#555555" stroke="#555555" points="1160.1,-43.94 1158,-37.94 1155.9,-43.94 1160.1,-43.94"/>
+</g>
+<!-- PTR_PERSON_NIL -->
+<g id="node29" class="node">
+<title>PTR_PERSON_NIL</title>
+<ellipse fill="#008000" stroke="black" cx="1111" cy="-552.64" rx="50.33" ry="18"/>
+<text text-anchor="middle" x="1111" y="-548.54" font-family="DejaVu Sans" font-size="13.00" fill="white">*Person?</text>
+</g>
+<!-- PTR_NULL&#45;&gt;PTR_PERSON_NIL -->
+<g id="edge43" class="edge">
+<title>PTR_NULL&#45;&gt;PTR_PERSON_NIL</title>
+<path fill="none" stroke="#555555" d="M1203.98,-642.89C1185.68,-625.32 1154.58,-595.47 1133.44,-575.18"/>
+<polygon fill="#555555" stroke="#555555" points="1134.9,-573.67 1129.12,-571.03 1131.99,-576.7 1134.9,-573.67"/>
+</g>
+<!-- PTR_S1_NIL -->
+<g id="node30" class="node">
+<title>PTR_S1_NIL</title>
+<ellipse fill="#008000" stroke="black" cx="1208" cy="-552.64" rx="30.37" ry="18"/>
+<text text-anchor="middle" x="1208" y="-548.54" font-family="DejaVu Sans" font-size="13.00" fill="white">*s1?</text>
+</g>
+<!-- PTR_NULL&#45;&gt;PTR_S1_NIL -->
+<g id="edge44" class="edge">
+<title>PTR_NULL&#45;&gt;PTR_S1_NIL</title>
+<path fill="none" stroke="#555555" d="M1217.18,-640.18C1215.39,-623.3 1212.64,-597.33 1210.61,-578.24"/>
+<polygon fill="#555555" stroke="#555555" points="1212.7,-578.03 1209.98,-572.29 1208.52,-578.48 1212.7,-578.03"/>
+</g>
+<!-- PTR_MORE_NIL -->
+<g id="node31" class="node">
+<title>PTR_MORE_NIL</title>
+<ellipse fill="#008000" stroke="black" cx="1300" cy="-552.64" rx="45.21" ry="18"/>
+<text text-anchor="middle" x="1300" y="-548.54" font-family="DejaVu Sans" font-size="13.00" fill="white">*s2?, …</text>
+</g>
+<!-- PTR_NULL&#45;&gt;PTR_MORE_NIL -->
+<g id="edge45" class="edge">
+<title>PTR_NULL&#45;&gt;PTR_MORE_NIL</title>
+<path fill="none" stroke="#555555" d="M1230.95,-642C1244.59,-624.55 1267.02,-595.85 1282.6,-575.91"/>
+<polygon fill="#555555" stroke="#555555" points="1284.22,-577.24 1286.26,-571.22 1280.92,-574.65 1284.22,-577.24"/>
+</g>
+<!-- PTR_ANY -->
+<g id="node25" class="node">
+<title>PTR_ANY</title>
+<ellipse fill="#008000" stroke="black" cx="962" cy="-552.64" rx="82.38" ry="28.99"/>
+<text text-anchor="middle" x="962" y="-556.79" font-family="DejaVu Sans" font-size="13.00" fill="white">*⊥:struct</text>
+<text text-anchor="middle" x="962" y="-540.29" font-family="DejaVu Sans" font-size="13.00" fill="white">[ptr any struct]</text>
+</g>
+<!-- PTR_ANY&#45;&gt;PTR_BOT -->
+<g id="edge46" class="edge">
+<title>PTR_ANY&#45;&gt;PTR_BOT</title>
+<path fill="none" stroke="#555555" d="M974.56,-523.53C1008.99,-446.47 1104.84,-231.98 1142.51,-147.66"/>
+<polygon fill="#555555" stroke="#555555" points="1144.4,-148.58 1144.93,-142.25 1140.56,-146.87 1144.4,-148.58"/>
+</g>
+<!-- PTR_ANY&#45;&gt;PTR_PERSON_NIL -->
+<!-- PTR_PERSON&#45;&gt;PTR_ANY -->
+<g id="edge37" class="edge">
+<title>PTR_PERSON&#45;&gt;PTR_ANY</title>
+<path fill="none" stroke="#555555" d="M962,-640.18C962,-626.3 962,-606.26 962,-588.96"/>
+<polygon fill="#555555" stroke="#555555" points="964.1,-589.25 962,-583.25 959.9,-589.25 964.1,-589.25"/>
+</g>
+<!-- PTR_PERSON&#45;&gt;PTR_S1 -->
+<!-- PTR_PERSON&#45;&gt;PTR_PERSON_NIL -->
+<g id="edge40" class="edge">
+<title>PTR_PERSON&#45;&gt;PTR_PERSON_NIL</title>
+<path fill="none" stroke="#555555" d="M983.67,-642.23C1009.89,-623.98 1054.1,-593.22 1082.92,-573.18"/>
+<polygon fill="#555555" stroke="#555555" points="1083.85,-575.09 1087.58,-569.94 1081.45,-571.64 1083.85,-575.09"/>
+</g>
+<!-- PTR_S1&#45;&gt;PTR_ANY -->
+<g id="edge38" class="edge">
+<title>PTR_S1&#45;&gt;PTR_ANY</title>
+<path fill="none" stroke="#555555" d="M1038.25,-642.45C1025.79,-627.94 1006.41,-605.36 990.3,-586.6"/>
+<polygon fill="#555555" stroke="#555555" points="991.91,-585.25 986.4,-582.07 988.72,-587.99 991.91,-585.25"/>
+</g>
+<!-- PTR_S1&#45;&gt;PTR_MORE -->
+<!-- PTR_S1&#45;&gt;PTR_S1_NIL -->
+<g id="edge41" class="edge">
+<title>PTR_S1&#45;&gt;PTR_S1_NIL</title>
+<path fill="none" stroke="#555555" d="M1072.08,-646.82C1101.29,-632.14 1152.34,-605.85 1169,-593.3 1176.35,-587.76 1183.64,-580.85 1189.88,-574.36"/>
+<polygon fill="#555555" stroke="#555555" points="1191.26,-575.96 1193.83,-570.14 1188.2,-573.09 1191.26,-575.96"/>
+</g>
+<!-- PTR_MORE&#45;&gt;PTR_NULL -->
+<!-- PTR_MORE&#45;&gt;PTR_ANY -->
+<g id="edge39" class="edge">
+<title>PTR_MORE&#45;&gt;PTR_ANY</title>
+<path fill="none" stroke="#555555" d="M1111.67,-643.32C1085.45,-627.61 1042.2,-601.69 1008.92,-581.75"/>
+<polygon fill="#555555" stroke="#555555" points="1010.35,-580.16 1004.12,-578.88 1008.19,-583.77 1010.35,-580.16"/>
+</g>
+<!-- PTR_MORE&#45;&gt;PTR_MORE_NIL -->
+<g id="edge42" class="edge">
+<title>PTR_MORE&#45;&gt;PTR_MORE_NIL</title>
+<path fill="none" stroke="#555555" d="M1160.16,-643.83C1182.97,-631.38 1217.31,-612.02 1246,-593.3 1255.42,-587.15 1265.42,-579.99 1274.23,-573.46"/>
+<polygon fill="#555555" stroke="#555555" points="1275.36,-575.24 1278.9,-569.97 1272.84,-571.88 1275.36,-575.24"/>
+</g>
+<!-- PTR_PERSON_NIL&#45;&gt;PTR_BOT -->
+<g id="edge47" class="edge">
+<title>PTR_PERSON_NIL&#45;&gt;PTR_BOT</title>
+<path fill="none" stroke="#555555" d="M1112.87,-534.18C1119.87,-468.84 1144.61,-238.01 1154.18,-148.67"/>
+<polygon fill="#555555" stroke="#555555" points="1156.26,-148.92 1154.81,-142.73 1152.09,-148.47 1156.26,-148.92"/>
+</g>
+<!-- PTR_PERSON_NIL&#45;&gt;PTR_S1_NIL -->
+<!-- PTR_S1_NIL&#45;&gt;PTR_BOT -->
+<g id="edge48" class="edge">
+<title>PTR_S1_NIL&#45;&gt;PTR_BOT</title>
+<path fill="none" stroke="#555555" d="M1206.04,-534.45C1198.64,-469.49 1172.28,-238.26 1162.08,-148.74"/>
+<polygon fill="#555555" stroke="#555555" points="1164.16,-148.51 1161.4,-142.79 1159.99,-148.99 1164.16,-148.51"/>
+</g>
+<!-- PTR_S1_NIL&#45;&gt;PTR_MORE_NIL -->
+<!-- PTR_MORE_NIL&#45;&gt;PTR_BOT -->
+<g id="edge49" class="edge">
+<title>PTR_MORE_NIL&#45;&gt;PTR_BOT</title>
+<path fill="none" stroke="#555555" d="M1294.43,-534.45C1273.34,-469.29 1198.07,-236.78 1169.3,-147.89"/>
+<polygon fill="#555555" stroke="#555555" points="1171.38,-147.49 1167.53,-142.43 1167.38,-148.78 1171.38,-147.49"/>
+</g>
+<!-- STRUCT_PERSON -->
+<g id="node34" class="node">
+<title>STRUCT_PERSON</title>
+<polygon fill="#90ee90" stroke="black" points="1436.5,-228.98 1369.5,-228.98 1369.5,-187.98 1436.5,-187.98 1436.5,-228.98"/>
+<text text-anchor="middle" x="1403" y="-212.63" font-family="DejaVu Sans" font-size="13.00">Person</text>
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+</g>
+<!-- STRUCT_TOP&#45;&gt;STRUCT_PERSON -->
+<g id="edge53" class="edge">
+<title>STRUCT_TOP&#45;&gt;STRUCT_PERSON</title>
+<path fill="none" stroke="#555555" d="M1468.98,-723.31C1455.09,-685.46 1433,-615.54 1433,-553.64 1433,-553.64 1433,-553.64 1433,-410.98 1433,-347.98 1418.48,-275.1 1409.64,-236.59"/>
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+<!-- STRUCT_S1 -->
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+<!-- STRUCT_TOP&#45;&gt;STRUCT_S1 -->
+<g id="edge54" class="edge">
+<title>STRUCT_TOP&#45;&gt;STRUCT_S1</title>
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+<!-- STRUCT_S2 -->
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+<!-- STRUCT_TOP&#45;&gt;STRUCT_S2 -->
+<g id="edge55" class="edge">
+<title>STRUCT_TOP&#45;&gt;STRUCT_S2</title>
+<path fill="none" stroke="#555555" d="M1492.66,-723.47C1508.62,-685.79 1534,-616.07 1534,-553.64 1534,-553.64 1534,-553.64 1534,-410.98 1534,-347.63 1551.91,-274.88 1562.81,-236.49"/>
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+<!-- STRUCT_MORE -->
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+<text text-anchor="middle" x="1662" y="-204.38" font-family="DejaVu Sans" font-size="13.00">…</text>
+</g>
+<!-- STRUCT_TOP&#45;&gt;STRUCT_MORE -->
+<g id="edge56" class="edge">
+<title>STRUCT_TOP&#45;&gt;STRUCT_MORE</title>
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+<!-- STRUCT_TOP&#45;&gt;MEM_TOP -->
+<!-- STRUCT_BOT -->
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+<title>STRUCT_BOT</title>
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+<!-- STRUCT_BOT&#45;&gt;BOT -->
+<g id="edge88" class="edge">
+<title>STRUCT_BOT&#45;&gt;BOT</title>
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+<!-- STRUCT_PERSON&#45;&gt;STRUCT_BOT -->
+<g id="edge57" class="edge">
+<title>STRUCT_PERSON&#45;&gt;STRUCT_BOT</title>
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+<polygon fill="#555555" stroke="#555555" points="1454.82,-147.22 1456.98,-141.24 1451.56,-144.57 1454.82,-147.22"/>
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+<!-- STRUCT_PERSON&#45;&gt;STRUCT_S1 -->
+<!-- STRUCT_S1&#45;&gt;STRUCT_BOT -->
+<g id="edge58" class="edge">
+<title>STRUCT_S1&#45;&gt;STRUCT_BOT</title>
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+<polygon fill="#555555" stroke="#555555" points="1482.1,-148.66 1480,-142.66 1477.9,-148.66 1482.1,-148.66"/>
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+<!-- STRUCT_S1&#45;&gt;STRUCT_S2 -->
+<!-- STRUCT_S2&#45;&gt;STRUCT_BOT -->
+<g id="edge59" class="edge">
+<title>STRUCT_S2&#45;&gt;STRUCT_BOT</title>
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+<polygon fill="#555555" stroke="#555555" points="1512.46,-143.67 1506.78,-140.8 1509.43,-146.58 1512.46,-143.67"/>
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+<!-- STRUCT_S2&#45;&gt;STRUCT_MORE -->
+<!-- STRUCT_MORE&#45;&gt;STRUCT_BOT -->
+<g id="edge60" class="edge">
+<title>STRUCT_MORE&#45;&gt;STRUCT_BOT</title>
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+<!-- MEM_ALIAS2 -->
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+<!-- MEM_TOP&#45;&gt;MEM_ALIAS2 -->
+<g id="edge63" class="edge">
+<title>MEM_TOP&#45;&gt;MEM_ALIAS2</title>
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+<!-- MEM_ALIAS3 -->
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+<!-- MEM_TOP&#45;&gt;MEM_ALIAS3 -->
+<g id="edge64" class="edge">
+<title>MEM_TOP&#45;&gt;MEM_ALIAS3</title>
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+<!-- MEM_MORE -->
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+<!-- MEM_TOP&#45;&gt;MEM_MORE -->
+<g id="edge65" class="edge">
+<title>MEM_TOP&#45;&gt;MEM_MORE</title>
+<path fill="none" stroke="#555555" d="M1812.51,-733.96C1834.85,-663.64 1918.78,-399.51 1944.48,-318.66"/>
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+<!-- MEM_TOP&#45;&gt;TUPLE_TOP -->
+<!-- MEM_BOT -->
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+<title>MEM_BOT</title>
+<ellipse fill="#00008b" stroke="black" cx="1811" cy="-111.99" rx="44.7" ry="18"/>
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+<!-- MEM_BOT&#45;&gt;BOT -->
+<g id="edge89" class="edge">
+<title>MEM_BOT&#45;&gt;BOT</title>
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+<!-- MEM_ALIAS2&#45;&gt;MEM_BOT -->
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+<title>MEM_ALIAS2&#45;&gt;MEM_BOT</title>
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+<!-- MEM_ALIAS2&#45;&gt;MEM_ALIAS3 -->
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+<title>MEM_ALIAS3&#45;&gt;MEM_BOT</title>
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+<!-- MEM_ALIAS3&#45;&gt;MEM_MORE -->
+<!-- MEM_MORE&#45;&gt;MEM_BOT -->
+<g id="edge68" class="edge">
+<title>MEM_MORE&#45;&gt;MEM_BOT</title>
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+<!-- TUPLE1 -->
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+<!-- TUPLE_TOP&#45;&gt;TUPLE1 -->
+<g id="edge71" class="edge">
+<title>TUPLE_TOP&#45;&gt;TUPLE1</title>
+<path fill="none" stroke="#555555" d="M2046.83,-734.05C2043.18,-680.39 2031.99,-515.78 2027.21,-445.42"/>
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+<!-- TUPLE2 -->
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+<!-- TUPLE_TOP&#45;&gt;TUPLE2 -->
+<g id="edge72" class="edge">
+<title>TUPLE_TOP&#45;&gt;TUPLE2</title>
+<path fill="none" stroke="#555555" d="M2049.89,-734.05C2055.41,-683.57 2071.67,-534.87 2079.98,-458.86"/>
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+<!-- TUPLEN -->
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+<!-- TUPLE_TOP&#45;&gt;TUPLEN -->
+<g id="edge73" class="edge">
+<title>TUPLE_TOP&#45;&gt;TUPLEN</title>
+<path fill="none" stroke="#555555" d="M2052.94,-734.05C2066.64,-686.28 2105.56,-550.54 2128.17,-471.69"/>
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+<!-- TUPLE_BOT -->
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+<title>TUPLE_BOT</title>
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+<!-- TUPLE_BOT&#45;&gt;BOT -->
+<g id="edge90" class="edge">
+<title>TUPLE_BOT&#45;&gt;BOT</title>
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+<!-- TUPLE1&#45;&gt;TUPLE_BOT -->
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+<title>TUPLE1&#45;&gt;TUPLE_BOT</title>
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+<!-- TUPLE1&#45;&gt;TUPLE2 -->
+<!-- TUPLE2&#45;&gt;TUPLE_BOT -->
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+<title>TUPLE2&#45;&gt;TUPLE_BOT</title>
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+<!-- TUPLE2&#45;&gt;TUPLEN -->
+<!-- TUPLEN&#45;&gt;TUPLE_BOT -->
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+<title>TUPLEN&#45;&gt;TUPLE_BOT</title>
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