Revert "Define __LIBGCC_DWARF_REG_SIZES_CONSTANT__ if DWARF register size is constant"

This reverts commit 97bbdb726aba76ead550e25061029cf0aa78671b.

4 files changed, 12 insertions, 60 deletions

diff --git a/gcc/c-family/c-cppbuiltin.cc b/gcc/c-family/c-cppbuiltin.cc
index 011478c..333f3e1 100644
--- a/gcc/c-family/c-cppbuiltin.cc
+++ b/gcc/c-family/c-cppbuiltin.cc
@@ -1521,12 +1521,6 @@ c_cpp_builtins (cpp_reader *pfile)
 #endif
       builtin_define_with_int_value ("__LIBGCC_DWARF_FRAME_REGISTERS__",
 				     DWARF_FRAME_REGISTERS);
-      {
-	int value = dwarf_reg_sizes_constant ();
-	if (value > 0)
-	  builtin_define_with_int_value ("__LIBGCC_DWARF_REG_SIZES_CONSTANT__",
-					 value);
-      }
 #ifdef EH_RETURN_STACKADJ_RTX
       cpp_define (pfile, "__LIBGCC_EH_RETURN_STACKADJ_RTX__");
 #endif
diff --git a/gcc/debug.h b/gcc/debug.h
index 4fe9f35..799d5e3 100644
--- a/gcc/debug.h
+++ b/gcc/debug.h
@@ -245,8 +245,6 @@ extern const struct gcc_debug_hooks vmsdbg_debug_hooks;
 
 /* Dwarf2 frame information.  */
 
-extern int dwarf_reg_sizes_constant ();
-
 extern void dwarf2out_begin_prologue (unsigned int, unsigned int,
 				      const char *);
 extern void dwarf2out_vms_end_prologue (unsigned int, const char *);
diff --git a/gcc/dwarf2cfi.cc b/gcc/dwarf2cfi.cc
index d5a27dc..4d2bd86 100644
--- a/gcc/dwarf2cfi.cc
+++ b/gcc/dwarf2cfi.cc
@@ -334,29 +334,6 @@ generate_dwarf_reg_sizes (poly_uint16 *sizes)
     targetm.init_dwarf_reg_sizes_extra (sizes);
 }
 
-/* Return 0 if the DWARF register sizes are not constant, otherwise
-   return the size constant.  */
-
-int
-dwarf_reg_sizes_constant ()
-{
-  poly_uint16 *sizes = XALLOCAVEC (poly_uint16, DWARF_FRAME_REGISTERS);
-  generate_dwarf_reg_sizes (sizes);
-
-  int result;
-  for (unsigned int i = 0; i < DWARF_FRAME_REGISTERS; i++)
-    {
-      unsigned short value;
-      if (!sizes[i].is_constant (&value))
-	return 0;
-      if (i == 0)
-	result = value;
-      else if (result != value)
-	return 0;
-    }
-  return result;
-}
-
 /* Generate code to initialize the dwarf register size table located
    at the provided ADDRESS.  */
 
diff --git a/libgcc/unwind-dw2.c b/libgcc/unwind-dw2.c
index c370121..eaceace 100644
--- a/libgcc/unwind-dw2.c
+++ b/libgcc/unwind-dw2.c
@@ -148,25 +148,9 @@ struct _Unwind_Context
   char by_value[__LIBGCC_DWARF_FRAME_REGISTERS__+1];
 };
 
-#ifdef __LIBGCC_DWARF_REG_SIZES_CONSTANT__
-static inline unsigned char
-dwarf_reg_size (int index __attribute__ ((__unused__)))
-{
-  return __LIBGCC_DWARF_REG_SIZES_CONSTANT__;
-}
-#else
 /* Byte size of every register managed by these routines.  */
 static unsigned char dwarf_reg_size_table[__LIBGCC_DWARF_FRAME_REGISTERS__+1];
 
-
-static inline unsigned char
-dwarf_reg_size (unsigned index)
-{
-  gcc_assert (index < sizeof (dwarf_reg_size_table));
-  return dwarf_reg_size_table[index];
-}
-#endif
-
 
 /* Read unaligned data from the instruction buffer.  */
 
@@ -248,7 +232,8 @@ _Unwind_GetGR (struct _Unwind_Context *context, int regno)
 #endif
 
   index = DWARF_REG_TO_UNWIND_COLUMN (regno);
-  size = dwarf_reg_size (index);
+  gcc_assert (index < (int) sizeof(dwarf_reg_size_table));
+  size = dwarf_reg_size_table[index];
   val = context->reg[index];
 
   if (_Unwind_IsExtendedContext (context) && context->by_value[index])
@@ -295,7 +280,8 @@ _Unwind_SetGR (struct _Unwind_Context *context, int index, _Unwind_Word val)
   void *ptr;
 
   index = DWARF_REG_TO_UNWIND_COLUMN (index);
-  size = dwarf_reg_size (index);
+  gcc_assert (index < (int) sizeof(dwarf_reg_size_table));
+  size = dwarf_reg_size_table[index];
 
   if (_Unwind_IsExtendedContext (context) && context->by_value[index])
     {
@@ -343,8 +329,9 @@ _Unwind_SetGRValue (struct _Unwind_Context *context, int index,
 		    _Unwind_Word val)
 {
   index = DWARF_REG_TO_UNWIND_COLUMN (index);
+  gcc_assert (index < (int) sizeof(dwarf_reg_size_table));
   /* Return column size may be smaller than _Unwind_Context_Reg_Val.  */
-  gcc_assert (dwarf_reg_size (index) <= sizeof (_Unwind_Context_Reg_Val));
+  gcc_assert (dwarf_reg_size_table[index] <= sizeof (_Unwind_Context_Reg_Val));
 
   context->by_value[index] = 1;
   context->reg[index] = _Unwind_Get_Unwind_Context_Reg_Val (val);
@@ -1400,7 +1387,7 @@ static inline void
 _Unwind_SetSpColumn (struct _Unwind_Context *context, void *cfa,
 		     _Unwind_SpTmp *tmp_sp)
 {
-  int size = dwarf_reg_size (__builtin_dwarf_sp_column ());
+  int size = dwarf_reg_size_table[__builtin_dwarf_sp_column ()];
 
   if (size == sizeof(_Unwind_Ptr))
     tmp_sp->ptr = (_Unwind_Ptr) cfa;
@@ -1586,13 +1573,11 @@ uw_advance_context (struct _Unwind_Context *context, _Unwind_FrameState *fs)
     }									   \
   while (0)
 
-#ifndef __LIBGCC_DWARF_REG_SIZES_CONSTANT__
 static inline void
 init_dwarf_reg_size_table (void)
 {
   __builtin_init_dwarf_reg_size_table (dwarf_reg_size_table);
 }
-#endif
 
 static void __attribute__((noinline))
 uw_init_context_1 (struct _Unwind_Context *context,
@@ -1611,18 +1596,16 @@ uw_init_context_1 (struct _Unwind_Context *context,
   code = uw_frame_state_for (context, &fs);
   gcc_assert (code == _URC_NO_REASON);
 
-#ifndef __LIBGCC_DWARF_REG_SIZES_CONSTANT__
-# if __GTHREADS
+#if __GTHREADS
   {
     static __gthread_once_t once_regsizes = __GTHREAD_ONCE_INIT;
     if (__gthread_once (&once_regsizes, init_dwarf_reg_size_table) != 0
 	&& dwarf_reg_size_table[0] == 0)
       init_dwarf_reg_size_table ();
   }
-# else
+#else
   if (dwarf_reg_size_table[0] == 0)
     init_dwarf_reg_size_table ();
-# endif
 #endif
 
   /* Force the frame state to use the known cfa value.  */
@@ -1699,20 +1682,20 @@ uw_install_context_1 (struct _Unwind_Context *current,
 	{
 	  _Unwind_Word w;
 	  _Unwind_Ptr p;
-	  if (dwarf_reg_size (i) == sizeof (_Unwind_Word))
+	  if (dwarf_reg_size_table[i] == sizeof (_Unwind_Word))
 	    {
 	      w = (_Unwind_Internal_Ptr) t;
 	      memcpy (c, &w, sizeof (_Unwind_Word));
 	    }
 	  else
 	    {
-	      gcc_assert (dwarf_reg_size (i) == sizeof (_Unwind_Ptr));
+	      gcc_assert (dwarf_reg_size_table[i] == sizeof (_Unwind_Ptr));
 	      p = (_Unwind_Internal_Ptr) t;
 	      memcpy (c, &p, sizeof (_Unwind_Ptr));
 	    }
 	}
       else if (t && c && t != c)
-	memcpy (c, t, dwarf_reg_size (i));
+	memcpy (c, t, dwarf_reg_size_table[i]);
     }
 
   /* If the current frame doesn't have a saved stack pointer, then we