X-Git-Url: https://git.stderr.nl/gitweb?a=blobdiff_plain;f=interpreters%2Fgit%2Fcompiler.h;fp=interpreters%2Fgit%2Fcompiler.h;h=4ee39c61856f66058e5a5a0e26be12837744b33a;hb=147a8cbf17f2b3379277bf7d37cda9866510f16c;hp=0000000000000000000000000000000000000000;hpb=7de488aa6a1709a4d5c59b5ff59862105c1748c5;p=rodin%2Fchimara.git

diff --git a/interpreters/git/compiler.h b/interpreters/git/compiler.h
new file mode 100644
index 0000000..4ee39c6
--- /dev/null
+++ b/interpreters/git/compiler.h
@@ -0,0 +1,108 @@
+// Header for compiler.c
+// $Id: compiler.h,v 1.11 2004/02/02 00:13:46 iain Exp $
+
+#ifndef GIT_COMPILER_H
+#define GIT_COMPILER_H
+
+// -------------------------------------------------------------
+// Types
+
+typedef enum
+{
+#define LABEL(foo) label_ ## foo,
+#include "labels.inc"
+    MAX_LABEL
+}
+Label;
+
+#ifdef USE_DIRECT_THREADING
+typedef void* Opcode; // Generated opcode: pointer to a label in exec().
+#else
+typedef Label Opcode;
+#endif
+
+typedef git_uint32* Block; // Generated code block: array of labels.
+
+// -------------------------------------------------------------
+// Settings
+
+extern int gPeephole; // Peephole optimisation of generated code?
+extern int gDebug;    // Insert debug statements into generated code?
+extern int gCacheRAM; // Keep RAM-based code in the JIT cache?
+
+// -------------------------------------------------------------
+// Compiling code
+
+extern const char* gLabelNames[];
+
+extern void initCompiler (size_t cacheSize);
+extern void shutdownCompiler ();
+
+extern void emitData (git_uint32);
+extern void emitFinalCode (Label);
+extern void emitConstBranch (Label op, git_uint32 address);
+
+extern void abortCompilation ();
+
+extern git_uint32 undoEmit();
+extern void nextInstructionIsReferenced ();
+
+extern Block peekAtEmittedStuff (int numOpcodes);
+
+// -------------------------------------------------------------
+// Accessing compiled code
+
+extern void pruneCodeCache (git_uint32 start, git_uint32 size);
+extern void resetCodeCache ();
+extern void compressCodeCache ();
+
+extern Block compile (git_uint32 pc);
+
+typedef struct HashNode HashNode;
+
+struct HashNode
+{
+    git_uint32 address;      // Glulx address for this entry.
+    git_sint16 codeOffset;   // Offset in 4-byte words from this hash node to the compiled code.
+    git_sint16 headerOffset; // Offset in 4-byte words from this hash node to the block header.
+    union {
+        int pad;             // This pad assures that PatchNode and HashNode are the same size.
+        HashNode * next;     // Next node in the same hash table slot.
+    } u;
+};
+
+typedef struct BlockHeader
+{
+    git_uint16 numHashNodes; // Number of lookup-able addresses in this block.
+    git_uint16 compiledSize; // Total size of this block, in 4-byte words.
+    git_uint32 glulxSize;    // Size of the glulx code this block represents, in bytes.
+    git_uint32 runCounter;   // Total number of opcodes executed in this block.
+}                            // (used to determine which blocks stay in the cache)
+BlockHeader;
+
+// This is the header for the block currently being executed --
+// that is, the one containing the return value of the last call
+// to getCode().
+extern BlockHeader * gBlockHeader;
+
+// Hash table for code lookup -- inlined for speed
+
+extern HashNode ** gHashTable; // Hash table of glulx address -> code.
+extern git_uint32 gHashSize;   // Number of slots in the hash table.
+
+GIT_INLINE Block getCode (git_uint32 pc)
+{
+    HashNode * n = gHashTable [pc & (gHashSize-1)];
+    while (n)
+    {
+        if (n->address == pc)
+        {
+            gBlockHeader = (BlockHeader*) ((git_uint32*)n + n->headerOffset);
+            return (git_uint32*)n + n->codeOffset;
+        }
+        n = n->u.next;
+    }
+    return compile (pc);
+}
+
+#endif // GIT_COMPILER_H