bare_instructions.rb: sp_inc is signed

* tool/ruby_vm/models/bare_instructions.rb (predefine_attributes):
  `sp_inc` attribute which may return negative values must be
  signed `rb_snum_t`, to be signed-expanded at type promotion.

* vm_insnhelper.h (ADJ_SP): removed the workaround for platforms
  where rb_num_t is wider than int.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62103 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

Author: nobu

tool/ruby_vm/models/bare_instructions.rb

@@ -128,7 +128,7 @@ def predefine_attributes
     generate_attribute 'rb_num_t', 'popn', pops.size
     generate_attribute 'rb_num_t', 'retn', rets.size
     generate_attribute 'rb_num_t', 'width', width
-    generate_attribute 'rb_num_t', 'sp_inc', rets.size - pops.size
+    generate_attribute 'rb_snum_t', 'sp_inc', rets.size - pops.size
     generate_attribute 'bool', 'handles_frame', false
   end
 

vm_insnhelper.h

@@ -101,22 +101,7 @@ enum vm_regan_acttype {
 #define DEC_SP(x)  (VM_REG_SP -= (COLLECT_USAGE_REGISTER_HELPER(SP, SET, (x))))
 #define SET_SV(x)  (*GET_SP() = (x))
   /* set current stack value as x */
-#ifdef _MSC_VER
-/* Workaround needed for adding negative number to a pointer */
-#define ADJ_SP(x)  do { \
-    rb_snum_t adj = (x); \
-    if (adj >= 0) { \
-        INC_SP(adj); \
-    } \
-    else { \
-        SIGNED_VALUE dec = -1; \
-        dec *= adj; \
-        DEC_SP(dec); \
-    } \
-} while (0)
-#else
 #define ADJ_SP(x)  INC_SP(x)
-#endif
 
 /* instruction sequence C struct */
 #define GET_ISEQ() (GET_CFP()->iseq)