# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1548547708 -3600
# Node ID 9c9bd4fccad4e817b657077c5ff06a67d93c5aba
# Parent  c77216b79bebf428513d0a51b3754ad88e6d29ab
Experiment with preallocation of floating point instances.

diff -r c77216b79beb -r 9c9bd4fccad4 templates/native/float.c
--- a/templates/native/float.c	Sat Jan 26 21:38:12 2019 +0100
+++ b/templates/native/float.c	Sun Jan 27 01:08:28 2019 +0100
@@ -28,6 +28,69 @@
 #include "progtypes.h"
 #include "main.h"
 
+/* A table of preallocated float instances. */
+
+struct float_table
+{
+    struct float_table *next;
+    char data[];
+};
+
+static struct float_table *next_float = 0;
+
+/* Preallocate some float instances. */
+
+static void preallocate_floats(int num)
+{
+    struct float_table *latest;
+    int i;
+
+    for (i = 0; i < num; i++)
+    {
+        /* Allocate a table entry. */
+
+        latest = (struct float_table *)
+                 __ALLOCATE(1, sizeof(struct float_table *) +
+                               __INSTANCESIZE(__builtins___float_float));
+
+        /* Reference the last entry from the new entry. */
+
+        latest->next = next_float;
+        next_float = latest;
+    }
+}
+
+static __attr new_float(double n)
+{
+    struct float_table *this_float;
+    __attr attr;
+
+    if (!next_float)
+        preallocate_floats(1000);
+
+    /* Reference the next preallocated entry. */
+
+    this_float = next_float;
+
+    /* Initialise the embedded instance. */
+
+    __init((__ref) &this_float->data,
+           &__INSTANCETABLE(__builtins___float_float),
+           &__builtins___float_float);
+
+    /* Populate the float with the value. */
+
+    attr = __ATTRVALUE(&this_float->data);
+    __set_trailing_data(attr, __builtins___float_float, n);
+
+    /* Make the next entry available and detach it from this one. */
+
+    next_float = this_float->next;
+    this_float->next = 0;
+
+    return attr;
+}
+
 /* Conversion of trailing data to a double-precision floating point number. */
 
 static double __TOFLOAT(__attr attr)
@@ -70,7 +133,7 @@
     /* self and other interpreted as float */
     double i = __TOFLOAT(self);
     double j = __TOFLOAT(other);
-    return __new_float(i + j);
+    return new_float(i + j);
 }
 
 __attr __fn_native_float_float_sub(__attr __self, __attr self, __attr other)
@@ -78,7 +141,7 @@
     /* self and other interpreted as float */
     double i = __TOFLOAT(self);
     double j = __TOFLOAT(other);
-    return __new_float(i - j);
+    return new_float(i - j);
 }
 
 __attr __fn_native_float_float_mul(__attr __self, __attr self, __attr other)
@@ -86,7 +149,7 @@
     /* self and other interpreted as float */
     double i = __TOFLOAT(self);
     double j = __TOFLOAT(other);
-    return __new_float(i * j);
+    return new_float(i * j);
 }
 
 __attr __fn_native_float_float_div(__attr __self, __attr self, __attr other)
@@ -94,7 +157,7 @@
     /* self and other interpreted as float */
     double i = __TOFLOAT(self);
     double j = __TOFLOAT(other);
-    return __new_float(i / j);
+    return new_float(i / j);
 }
 
 __attr __fn_native_float_float_mod(__attr __self, __attr self, __attr other)
@@ -102,14 +165,14 @@
     /* self and other interpreted as float */
     double i = __TOFLOAT(self);
     double j = __TOFLOAT(other);
-    return __new_float(fmod(i, j));
+    return new_float(fmod(i, j));
 }
 
 __attr __fn_native_float_float_neg(__attr __self, __attr self)
 {
     /* self interpreted as float */
     double i = __TOFLOAT(self);
-    return __new_float(-i);
+    return new_float(-i);
 }
 
 __attr __fn_native_float_float_pow(__attr __self, __attr self, __attr other)
@@ -128,7 +191,7 @@
         __raise_overflow_error();
 
     /* Return the result. */
-    return __new_float(result);
+    return new_float(result);
 }
 
 __attr __fn_native_float_float_le(__attr __self, __attr self, __attr other)
diff -r c77216b79beb -r 9c9bd4fccad4 templates/progops.h
--- a/templates/progops.h	Sat Jan 26 21:38:12 2019 +0100
+++ b/templates/progops.h	Sun Jan 27 01:08:28 2019 +0100
@@ -25,6 +25,7 @@
 
 /* Generic instantiation operations, defining common members. */
 
+void __init(__ref obj, const __table * table, __ref cls);
 __attr __new(const __table *table, __ref cls, size_t size, int immutable);
 __attr __new_wrapper(__attr context, __attr attr);