more 386 runtime - can run tiny c programs.
R=r
DELTA=1926 (1727 added, 168 deleted, 31 changed)
OCL=26876
CL=26878
diff --git a/src/runtime/mheapmap32.c b/src/runtime/mheapmap32.c
new file mode 100644
index 0000000..420ca2d
--- /dev/null
+++ b/src/runtime/mheapmap32.c
@@ -0,0 +1,96 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Heap map, 32-bit version
+// See malloc.h and mheap.c for overview.
+
+#include "runtime.h"
+#include "malloc.h"
+
+// 3-level radix tree mapping page ids to Span*.
+void
+MHeapMap_Init(MHeapMap *m, void *(*allocator)(size_t))
+{
+ m->allocator = allocator;
+}
+
+MSpan*
+MHeapMap_Get(MHeapMap *m, PageID k)
+{
+ int32 i1, i2;
+
+ i2 = k & MHeapMap_Level2Mask;
+ k >>= MHeapMap_Level2Bits;
+ i1 = k & MHeapMap_Level1Mask;
+ k >>= MHeapMap_Level1Bits;
+ if(k != 0)
+ throw("MHeapMap_Get");
+
+ return m->p[i1]->s[i2];
+}
+
+MSpan*
+MHeapMap_GetMaybe(MHeapMap *m, PageID k)
+{
+ int32 i1, i2;
+ MHeapMapNode2 *p2;
+
+ i2 = k & MHeapMap_Level2Mask;
+ k >>= MHeapMap_Level2Bits;
+ i1 = k & MHeapMap_Level1Mask;
+ k >>= MHeapMap_Level1Bits;
+ if(k != 0)
+ throw("MHeapMap_Get");
+
+ p2 = m->p[i1];
+ if(p2 == nil)
+ return nil;
+ return p2->s[i2];
+}
+
+void
+MHeapMap_Set(MHeapMap *m, PageID k, MSpan *s)
+{
+ int32 i1, i2;
+
+ i2 = k & MHeapMap_Level2Mask;
+ k >>= MHeapMap_Level2Bits;
+ i1 = k & MHeapMap_Level1Mask;
+ k >>= MHeapMap_Level1Bits;
+ if(k != 0)
+ throw("MHeapMap_Set");
+
+ m->p[i1]->s[i2] = s;
+}
+
+// Allocate the storage required for entries [k, k+1, ..., k+len-1]
+// so that Get and Set calls need not check for nil pointers.
+bool
+MHeapMap_Preallocate(MHeapMap *m, PageID k, uintptr len)
+{
+ uintptr end;
+ int32 i1;
+ MHeapMapNode2 *p2;
+
+ end = k+len;
+ while(k < end) {
+ if((k >> MHeapMap_TotalBits) != 0)
+ return false;
+ i1 = (k >> MHeapMap_Level2Bits) & MHeapMap_Level1Mask;
+
+ // first-level pointer
+ if(m->p[i1] == nil) {
+ p2 = m->allocator(sizeof *p2);
+ if(p2 == nil)
+ return false;
+ sys_memclr((byte*)p2, sizeof *p2);
+ m->p[i1] = p2;
+ }
+
+ // advance key past this leaf node
+ k = ((k >> MHeapMap_Level2Bits) + 1) << MHeapMap_Level2Bits;
+ }
+ return true;
+}
+
