Squashed commit of the following:

commit c05d7df4f9c90984d2c04126772be3fee1d81fd1
Author: Cliff Click <cliffc@acm.org>
Date:   Thu Aug 20 10:52:58 2026 -0700

    Fix local frefs, deferred inlining, and sys FileIO support

    - Defer non-trivial inlining out of CallEnd idealization and run it from IterPeeps after normal peepholes reach a fixed point.
    - Keep forward refs local to their lexical scope, promote them outward on scope pop, and track created FRefNodes directly for dependency  discovery.
    - Preserve loop scope shape when frefs are first seen inside loop bodies.
    - Treat frefs as final constants from creation and force lazy self lookups before implicit calls.
    - Reset imported pointer/struct types conservatively for post-parse Iter.
    - Pin Start-owned global machine value chains and clone global constants per function during GCM.
    - Improve late ASM printing before encoding and namespace constant-pool symbols.
    - Add optional regalloc function-local edge verifier and improve empty-mask splitting for multi-def/fixed-register LRGs.
    - Add sys array compare, safer array copy bounds, libc open/creat/close/unlink bindings, aryu8.str0, and higher-level sys.io file operations.
    - Add docs/examples/FileIO.smp and a Chapter25 FileIO test.
    - Update spill/code-size goldens after the allocator and scheduling changes.

commit ef5316979732ac118612d310b75923c8f59ecdc1
Author: Cliff Click <cliffc@acm.org>
Date:   Fri Aug 14 16:29:56 2026 -0700

    Dijkstra uses bitset.

    TestC.exec for repeated test runs with different stdins.
    Support &= and |= op-update forms.

commit 728a527587f19bb49860f02ae5ac5968ab01ae33
Author: Cliff Click <cliffc@acm.org>
Date:   Fri Aug 14 12:13:28 2026 -0700

    Fix live demo

commit e4c069b9ef2cbfafe28d8edfcbff55396cde085e
Author: Cliff Click <cliffc@acm.org>
Date:   Fri Aug 14 09:52:24 2026 -0700

    Update Dijkstra.smp

commit b8015739b4056e3f7a715a030e846a441021a9f1
Author: Cliff Click <cliffc@acm.org>
Date:   Fri Aug 14 09:41:17 2026 -0700

    Better looking Dijkstra

commit 7cce587804c6169b24829e0b5bdc10be94357a31
Author: Cliff Click <cliffc@acm.org>
Date:   Fri Aug 14 09:33:33 2026 -0700

    Fix CmpMemX86 encoding

    Use sys.aryu8 for number printing

commit 310b5d8c9978a3b09622a4b89dac97f0e5e6f3fb
Author: Cliff Click <cliffc@acm.org>
Date:   Fri Aug 14 09:04:58 2026 -0700

    Progress dijlstra

    Fix NotX86 encoding.  Allow Not-sinking through Phis; the Nots both take Scalar and might take different types (ptr vs int).  Better guard installing during && || opers.
    Drop the csv parse flavor in sys lib.

commit 5917d5322521dd5e762c4698d34e5d7ac9b3a37f
Author: Cliff Click <cliffc@acm.org>
Date:   Thu Aug 13 14:44:12 2026 -0700

    missed

commit da35ad4d8a330559a21c04ae6326536e0fd62c48
Author: Cliff Click <cliffc@acm.org>
Date:   Thu Aug 13 14:43:42 2026 -0700

    Major cleanup of allocation

    All the graph-gen is moved to the <ctor> declaration and not at the alloc site.

commit c4223216099ccbc526d282bb263972532d48c5b2
Author: Cliff Click <cliffc@acm.org>
Date:   Thu Aug 13 13:26:01 2026 -0700

    Some work from Dykstra (more coming)

commit a03bc567f61dc7e4355e453ee4be16ac2528d1ab
Author: Cliff Click <cliffc@acm.org>
Date:   Thu Aug 13 09:32:55 2026 -0700

    Spill correctness and improvements

    Had the callee-save pick-risky backwards vs cloneables.

commit 2d306e4430225f916cb7fb999f4926e52f6fb70a
Author: Cliff Click <cliffc@acm.org>
Date:   Wed Aug 12 19:40:04 2026 -0700

    Tighter parser handling of missing fields

    Bug fix add libc.errno, read can return -1, sys.ary exists

commit b7eeefda4cafa1e86153170dca6f13d45ef63f69
Author: Cliff Click <cliffc@acm.org>
Date:   Wed Aug 12 16:22:48 2026 -0700

    Printer improvements

commit 8b9112226f1d2d1c843b080eecefe0d5ddc1f8cf
Author: Cliff Click <cliffc@acm.org>
Date:   Wed Aug 12 15:30:46 2026 -0700

    Remove GLB

commit ae566f5c610b9c30831906d3f024901d8930a227
Author: Cliff Click <cliffc@acm.org>
Date:   Wed Aug 12 14:38:51 2026 -0700

    Add Capitalize example

    Rename Ary to ary.
    Fix bug || carrying state along.
    Fix bug load-array removing control.
    Add sys.char tolower/upper

1 files changed, 73 insertions, 0 deletions

diff --git a/chapter25/docs/examples/Dijkstra.smp b/chapter25/docs/examples/Dijkstra.smp
new file mode 100644
index 00000000..57e1fad4
--- /dev/null
+++ b/chapter25/docs/examples/Dijkstra.smp
@@ -0,0 +1,73 @@
+// -*- mode: java;  -*-
+
+// An implementation of
+// https://sampleprograms.io/projects/dijkstra/
+
+val shortestPath = { sys.aryi64 matrix, int nodes, int src, int dst ->
+    i64 infinity = (1 << 63)-1;
+    var dist = new i64[nodes];
+    var visited = new sys.adt.bitset();
+    // All nodes are infinitely far from each other
+    for( int i=0; i<nodes; i++ ) dist[i] = infinity;
+    // Starting point is zero far from starting point
+    dist[src] = 0;
+
+    i64 result = -1;
+    int count = 0;
+    while( count < nodes && result < 0 ) {
+        int nearest = -1;
+        i64 best = infinity;
+        for( int node=0; node<nodes; node++ )
+            if( !visited.get(node) && dist[node] < best ) {
+                nearest = node;
+                best = dist[node];
+            }
+        if( nearest < 0 ) count = nodes;
+        else {
+            if( nearest == dst ) return best;
+            visited.set(nearest);
+            for( int node=0; node<nodes; node++ ) {
+                i64 weight = matrix.get(nearest*nodes + node);
+                if( weight > 0 && !visited.get(node) && best+weight < dist[node] )
+                    dist[node] = best+weight;
+            }
+        }
+        count++;
+    }
+    return result;
+};
+
+val usage = { ->
+    sys.io.p("Usage: please provide three inputs: a serialized matrix, a source node and a destination node\n");
+    return 0;
+};
+
+val main = { u8[~][] args ->
+    // Exactly 3 args
+    if( args# != 4 ) return usage();
+    // First is a serialized square matrix of positive numbers
+    var matrix = sys.aryi64.parseAryI64(args[1]);
+    if( !matrix ) return usage();
+    if( !matrix.len ) return usage();
+    // All numbers are positive
+    for( int i=0; i<matrix.len; i++ )
+        if( matrix.get(i) < 0 ) return usage();
+    // Matrix is square
+    int nodes = 0;
+    while( nodes*nodes < matrix.len ) nodes++;
+    if( nodes*nodes != matrix.len )
+        return usage();         // Not a square matrix
+
+    // src,dst are values within the matrix
+    i64 src = sys.aryu8.atoi(args[2]);
+    i64 dst = sys.aryu8.atoi(args[3]);
+    if( src < 0 || src >= nodes || dst < 0 || dst >= nodes )
+        return usage();         // Source and destination land within the graph
+
+     i64 cost = shortestPath(matrix,nodes,src,dst);
+     if( cost >= 0 ) {
+         new sys.aryu8().num(cost).add('\n').write(1);
+         return 0;
+     }
+    return usage();
+};