Charles G. Waldman <cgw@fnal.gov>:

Add the EXTENDED_ARG opcode to the virtual machine, allowing 32-bit
arguments to opcodes instead of being forced to stick to the 16-bit
limit.  This is especially useful for machine-generated code, which
can be too long for the SET_LINENO parameter to fit into 16 bits.

This closes the implementation portion of SourceForge patch #100893.

diff --git a/Include/node.h b/Include/node.h
index affa8cd6aa9ff3e276bd4b4e755bdecd5032ccd1..96eb350f0a9ed1dd1bfecfbd02efb0d98044642e 100644 (file)
--- a/Include/node.h
+++ b/Include/node.h
@@ -19,8 +19,8 @@ extern "C" {
 typedef struct _node {
     short              n_type;
     char               *n_str;
-    short              n_lineno;
-    short              n_nchildren;
+    int                        n_lineno;
+    int                        n_nchildren;
     struct _node       *n_child;
 } node;
 

diff --git a/Include/opcode.h b/Include/opcode.h
index a7b642ab16bece77fc48fab196f2d928f788faff..f900aa958636bd92f701ba02de49c018f03f3886 100644 (file)
--- a/Include/opcode.h
+++ b/Include/opcode.h
@@ -130,6 +130,9 @@ redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 #define CALL_FUNCTION_KW           141 /* #args + (#kwargs<<8) */
 #define CALL_FUNCTION_VAR_KW       142 /* #args + (#kwargs<<8) */
 
+/* Support for opargs more than 16 bits long */
+#define EXTENDED_ARG  143
+
 /* Comparison operator codes (argument to COMPARE_OP) */
 enum cmp_op {LT, LE, EQ, NE, GT, GE, IN, NOT_IN, IS, IS_NOT, EXC_MATCH, BAD};
 

diff --git a/Lib/dis.py b/Lib/dis.py
index 3a80e741f73227301489ffeda554ee00747caac1..9fc9d3005945a5870ee32041c65edbfbd77a812d 100644 (file)
--- a/Lib/dis.py
+++ b/Lib/dis.py
@@ -56,6 +56,7 @@ def disassemble(co, lasti=-1):
        labels = findlabels(code)
        n = len(code)
        i = 0
+       extended_arg = 0
        while i < n:
                c = code[i]
                op = ord(c)
@@ -68,8 +69,11 @@ def disassemble(co, lasti=-1):
                print string.ljust(opname[op], 20),
                i = i+1
                if op >= HAVE_ARGUMENT:
-                       oparg = ord(code[i]) + ord(code[i+1])*256
+                       oparg = ord(code[i]) + ord(code[i+1])*256 + extended_arg
+                       extended_arg = 0
                        i = i+2
+                       if op == EXTENDED_ARG:
+                               extended_arg = oparg*65536L
                        print string.rjust(`oparg`, 5),
                        if op in hasconst:
                                print '(' + `co.co_consts[oparg]` + ')',
@@ -258,6 +262,8 @@ def_op('CALL_FUNCTION_VAR', 140)     # #args + (#kwargs << 8)
 def_op('CALL_FUNCTION_KW', 141)      # #args + (#kwargs << 8)
 def_op('CALL_FUNCTION_VAR_KW', 142)  # #args + (#kwargs << 8)
 
+def_op('EXTENDED_ARG', 143) 
+EXTENDED_ARG = 143
 
 def _test():
        """Simple test program to disassemble a file."""

diff --git a/Parser/node.c b/Parser/node.c
index 910192d3ac612bcf35d05dbab7977f3df9738088..6844965ea837fe77410a3124becaf4199d84148e 100644 (file)
--- a/Parser/node.c
+++ b/Parser/node.c
@@ -8,7 +8,12 @@ See the file "Misc/COPYRIGHT" for information on usage and
 redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 ******************************************************************/
 
+#ifdef HAVE_LIMITS_H
 #include <limits.h>
+#endif
+#ifndef INT_MAX
+#define INT_MAX 2147483647
+#endif
 
 /* Parse tree node implementation */
 
@@ -39,7 +44,7 @@ PyNode_AddChild(register node *n1, int type, char *str, int lineno)
        register int nch = n1->n_nchildren;
        register int nch1 = nch+1;
        register node *n;
-       if (nch == SHRT_MAX || nch < 0)
+       if (nch == INT_MAX || nch < 0)
                return E_OVERFLOW;
        if (XXXROUNDUP(nch) < nch1) {
                n = n1->n_child;

diff --git a/Python/ceval.c b/Python/ceval.c
index 23c477b4875488893c787517091a247c9d4e41b9..fb7b5bcb2801ec13ab91b77b8f6b7cc758622b4b 100644 (file)
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -613,6 +613,7 @@ eval_code2(PyCodeObject *co, PyObject *globals, PyObject *locals,
                opcode = NEXTOP();
                if (HAS_ARG(opcode))
                        oparg = NEXTARG();
+         dispatch_opcode:
 #ifdef DYNAMIC_EXECUTION_PROFILE
 #ifdef DXPAIRS
                dxpairs[lastopcode][opcode]++;
@@ -1750,6 +1751,11 @@ eval_code2(PyCodeObject *co, PyObject *globals, PyObject *locals,
                        if (x != NULL) continue;
                        break;
 
+               case EXTENDED_ARG:
+                       opcode = NEXTOP();
+                       oparg = oparg<<16 | NEXTARG();
+                       goto dispatch_opcode;
+                       break;
 
                default:
                        fprintf(stderr,

diff --git a/Python/compile.c b/Python/compile.c
index f239bb6a8b70e9cd91009023a52e5367359ef5e5..3b7c87af7646caf19b271c5da7f37990f936441f 100644 (file)
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -36,6 +36,9 @@ redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 #ifdef HAVE_LIMITS_H
 #include <limits.h>
 #endif
+#ifndef INT_MAX
+#define INT_MAX 2147483647
+#endif
 
 /* Three symbols from graminit.h are also defined in Python.h, with
    Py_ prefixes to their names.  Python.h can't include graminit.h
@@ -572,11 +575,17 @@ com_set_lineno(struct compiling *c, int lineno)
 static void
 com_addoparg(struct compiling *c, int op, int arg)
 {
+       int extended_arg = arg >> 16;
        if (op == SET_LINENO) {
                com_set_lineno(c, arg);
                if (Py_OptimizeFlag)
                        return;
        }
+       if (extended_arg){
+               com_addbyte(c, EXTENDED_ARG);
+               com_addint(c, extended_arg);
+               arg &= 0xffff;
+       }
        com_addbyte(c, op);
        com_addint(c, arg);
 }
@@ -606,7 +615,14 @@ com_backpatch(struct compiling *c, int anchor)
                prev = code[anchor] + (code[anchor+1] << 8);
                dist = target - (anchor+2);
                code[anchor] = dist & 0xff;
-               code[anchor+1] = dist >> 8;
+               dist >>= 8;
+               code[anchor+1] = dist;
+               dist >>= 8;
+               if (dist) {
+                       com_error(c, PyExc_SystemError,
+                                 "com_backpatch: offset too large");
+                       break;
+               }
                if (!prev)
                        break;
                anchor -= prev;
@@ -3364,6 +3380,7 @@ optimize(struct compiling *c)
                        break;
                if (HAS_ARG(opcode))
                        oparg = NEXTARG();
+         dispatch_opcode1:
                switch (opcode) {
                case STORE_NAME:
                case DELETE_NAME:
@@ -3374,6 +3391,11 @@ optimize(struct compiling *c)
                case EXEC_STMT:
                        c->c_flags &= ~CO_OPTIMIZED;
                        break;
+               case EXTENDED_ARG:
+                       opcode = NEXTOP();
+                       oparg = oparg<<16 | NEXTARG();
+                       goto dispatch_opcode1;
+                       break;
                }
        }
        
@@ -3389,6 +3411,7 @@ optimize(struct compiling *c)
                        break;
                if (HAS_ARG(opcode))
                        oparg = NEXTARG();
+         dispatch_opcode2:
                if (opcode == LOAD_NAME ||
                    opcode == STORE_NAME ||
                    opcode == DELETE_NAME) {
@@ -3403,13 +3426,20 @@ optimize(struct compiling *c)
                                continue;
                        }
                        i = PyInt_AsLong(v);
+                       if (i >> 16) /* too big for 2 bytes */
+                               continue;
                        switch (opcode) {
                        case LOAD_NAME: cur_instr[0] = LOAD_FAST; break;
                        case STORE_NAME: cur_instr[0] = STORE_FAST; break;
                        case DELETE_NAME: cur_instr[0] = DELETE_FAST; break;
                        }
                        cur_instr[1] = i & 0xff;
-                       cur_instr[2] = (i>>8) & 0xff;
+                       cur_instr[2] = i >> 8;
+               }
+               if (opcode == EXTENDED_ARG) {
+                       opcode = NEXTOP();
+                       oparg = oparg<<16 | NEXTARG();
+                       goto dispatch_opcode2;
                }
        }