During class file generation, generate_classfile occasionally writes

out a bunch of data and then skips backwards to fill in blanks.  When
configured with --enable-checking, this patching up will often trip
the checking code.  This change introduces UNSAFE_PUTx macros which
never use CHECK_PUT.  These should only be used in cases we know
CHECK_PUT will fail.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@29854 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/java/ChangeLog b/gcc/java/ChangeLog
index 18030fc..00ea759 100644 (file)
--- a/gcc/java/ChangeLog
+++ b/gcc/java/ChangeLog
@@ -1,3 +1,11 @@
+1999-10-07  Anthony Green  <green@cygnus.com>
+
+       * jcf-write.c (generate_classfile): Use UNSAFE_PUTx in cases
+       where CHECK_PUT may fail for valid reasons.
+
+       * jcf-write.c (UNSAFE_PUT1, UNSAFE_PUT2, UNSAFE_PUT3,
+       UNSAFE_PUTN): New macros.
+
 1999-10-04  Tom Tromey  <tromey@cygnus.com>
 
        * lex.h (BUILD_OPERATOR2): Return ASSIGN_ANY_TK in `lite' case as

diff --git a/gcc/java/jcf-write.c b/gcc/java/jcf-write.c
index 91567d0..5918757 100644 (file)
--- a/gcc/java/jcf-write.c
+++ b/gcc/java/jcf-write.c
@@ -358,6 +358,13 @@ CHECK_PUT(ptr, state, i)
 #define PUT4(X)  (PUT2((X) >> 16), PUT2((X) & 0xFFFF))
 #define PUTN(P, N)  (CHECK_PUT(ptr, state, N), memcpy(ptr, P, N), ptr += (N))
 
+/* There are some cases below where CHECK_PUT is guaranteed to fail.
+   Use the following macros in those specific cases.  */
+#define UNSAFE_PUT1(X)  (*ptr++ = (X))
+#define UNSAFE_PUT2(X)  (UNSAFE_PUT1((X) >> 8), UNSAFE_PUT1((X) & 0xFF))
+#define UNSAFE_PUT4(X)  (UNSAFE_PUT2((X) >> 16), UNSAFE_PUT2((X) & 0xFFFF))
+#define UNSAFE_PUTN(P, N)  (memcpy(ptr, P, N), ptr += (N))
+
 \f
 /* Allocate a new chunk on obstack WORK, and link it in after LAST.
    Set the data and size fields to DATA and SIZE, respectively.
@@ -2807,7 +2814,7 @@ generate_classfile (clas, state)
        }
       fields_count++;
     }
-  ptr = fields_count_ptr;  PUT2 (fields_count);
+  ptr = fields_count_ptr;  UNSAFE_PUT2 (fields_count);
 
   ptr = methods_count_ptr = append_chunk (NULL, 2, state);
   PUT2 (0);
@@ -2873,10 +2880,10 @@ generate_classfile (clas, state)
              code_attributes_count++;
              i += 8 + 10 * state->lvar_count;
            }
-         PUT4 (i); /* attribute_length */
-         PUT2 (state->code_SP_max);  /* max_stack */
-         PUT2 (localvar_max);  /* max_locals */
-         PUT4 (state->code_length);
+         UNSAFE_PUT4 (i); /* attribute_length */
+         UNSAFE_PUT2 (state->code_SP_max);  /* max_stack */
+         UNSAFE_PUT2 (localvar_max);  /* max_locals */
+         UNSAFE_PUT4 (state->code_length);
 
          /* Emit the exception table. */
          ptr = append_chunk (NULL, 2 + 8 * state->num_handlers, state);
@@ -2966,7 +2973,7 @@ generate_classfile (clas, state)
       methods_count++;
       current_function_decl = save_function;
     }
-  ptr = methods_count_ptr;  PUT2 (methods_count);
+  ptr = methods_count_ptr;  UNSAFE_PUT2 (methods_count);
 
   source_file = DECL_SOURCE_FILE (TYPE_NAME (clas));
   for (ptr = source_file;  ;  ptr++)