tm.texi.in (PIC_OFFSET_TABLE_REG_CALL_CLOBBERED): Document to be zero or nonzero.

2010-08-20  Joseph Myers  <joseph@codesourcery.com>

	gcc/
	* doc/tm.texi.in (PIC_OFFSET_TABLE_REG_CALL_CLOBBERED): Document to
	be zero or nonzero.
	* doc/tm.texi: Regenerate.
	* defaults.h (PIC_OFFSET_TABLE_REG_CALL_CLOBBERED): Define.
	* df-scan.c (df_get_exit_block_use_set), reginfo.c
	(init_reg_sets_1), rtlanal.c (rtx_unstable_p, rtx_varies_p):
	Handle new PIC_OFFSET_TABLE_REG_CALL_CLOBBERED semantics.
	* config/ia64/ia64.h (PIC_OFFSET_TABLE_REG_CALL_CLOBBERED): Define
	to 1.

From-SVN: r163399

8 files changed, 29 insertions, 18 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 3176285..11a82db 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,15 @@
+2010-08-20  Joseph Myers  <joseph@codesourcery.com>
+
+	* doc/tm.texi.in (PIC_OFFSET_TABLE_REG_CALL_CLOBBERED): Document to
+	be zero or nonzero.
+	* doc/tm.texi: Regenerate.
+	* defaults.h (PIC_OFFSET_TABLE_REG_CALL_CLOBBERED): Define.
+	* df-scan.c (df_get_exit_block_use_set), reginfo.c
+	(init_reg_sets_1), rtlanal.c (rtx_unstable_p, rtx_varies_p):
+	Handle new PIC_OFFSET_TABLE_REG_CALL_CLOBBERED semantics.
+	* config/ia64/ia64.h (PIC_OFFSET_TABLE_REG_CALL_CLOBBERED): Define
+	to 1.
+
 2010-08-20  Olivier Hainque  <hainque@adacore.com>
 
 	* config/sparc/sparc.c (sparc_asm_function_epilogue): Don't output
diff --git a/gcc/config/ia64/ia64.h b/gcc/config/ia64/ia64.h
index 39fa25c..b43d075 100644
--- a/gcc/config/ia64/ia64.h
+++ b/gcc/config/ia64/ia64.h
@@ -1359,7 +1359,7 @@ do {									\
 /* Define this macro if the register defined by `PIC_OFFSET_TABLE_REGNUM' is
    clobbered by calls.  */
 
-#define PIC_OFFSET_TABLE_REG_CALL_CLOBBERED
+#define PIC_OFFSET_TABLE_REG_CALL_CLOBBERED 1
 
 
 /* The Overall Framework of an Assembler File.  */
diff --git a/gcc/defaults.h b/gcc/defaults.h
index 7aa227c..aaf6ea6 100644
--- a/gcc/defaults.h
+++ b/gcc/defaults.h
@@ -722,6 +722,10 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #define PIC_OFFSET_TABLE_REGNUM INVALID_REGNUM
 #endif
 
+#ifndef PIC_OFFSET_TABLE_REG_CALL_CLOBBERED
+#define PIC_OFFSET_TABLE_REG_CALL_CLOBBERED 0
+#endif
+
 #ifndef TARGET_DLLIMPORT_DECL_ATTRIBUTES
 #define TARGET_DLLIMPORT_DECL_ATTRIBUTES 0
 #endif
diff --git a/gcc/df-scan.c b/gcc/df-scan.c
index b4633ab..8b17ae2 100644
--- a/gcc/df-scan.c
+++ b/gcc/df-scan.c
@@ -4032,14 +4032,13 @@ df_get_exit_block_use_set (bitmap exit_block_uses)
 #endif
     }
 
-#ifndef PIC_OFFSET_TABLE_REG_CALL_CLOBBERED
   /* Many architectures have a GP register even without flag_pic.
      Assume the pic register is not in use, or will be handled by
      other means, if it is not fixed.  */
-  if ((unsigned) PIC_OFFSET_TABLE_REGNUM != INVALID_REGNUM
+  if (!PIC_OFFSET_TABLE_REG_CALL_CLOBBERED
+      && (unsigned) PIC_OFFSET_TABLE_REGNUM != INVALID_REGNUM
       && fixed_regs[PIC_OFFSET_TABLE_REGNUM])
     bitmap_set_bit (exit_block_uses, PIC_OFFSET_TABLE_REGNUM);
-#endif
 
   /* Mark all global registers, and all registers used by the
      epilogue as being live at the end of the function since they
diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi
index 3e38618..7e8765b 100644
--- a/gcc/doc/tm.texi
+++ b/gcc/doc/tm.texi
@@ -7128,8 +7128,9 @@ when @code{flag_pic} is true).
 @end defmac
 
 @defmac PIC_OFFSET_TABLE_REG_CALL_CLOBBERED
-Define this macro if the register defined by
-@code{PIC_OFFSET_TABLE_REGNUM} is clobbered by calls.  Do not define
+A C expression that is nonzero if the register defined by
+@code{PIC_OFFSET_TABLE_REGNUM} is clobbered by calls.  If not defined,
+the default is zero.  Do not define
 this macro if @code{PIC_OFFSET_TABLE_REGNUM} is not defined.
 @end defmac
 
diff --git a/gcc/doc/tm.texi.in b/gcc/doc/tm.texi.in
index 6358916..4d13cbe 100644
--- a/gcc/doc/tm.texi.in
+++ b/gcc/doc/tm.texi.in
@@ -7123,8 +7123,9 @@ when @code{flag_pic} is true).
 @end defmac
 
 @defmac PIC_OFFSET_TABLE_REG_CALL_CLOBBERED
-Define this macro if the register defined by
-@code{PIC_OFFSET_TABLE_REGNUM} is clobbered by calls.  Do not define
+A C expression that is nonzero if the register defined by
+@code{PIC_OFFSET_TABLE_REGNUM} is clobbered by calls.  If not defined,
+the default is zero.  Do not define
 this macro if @code{PIC_OFFSET_TABLE_REGNUM} is not defined.
 @end defmac
 
diff --git a/gcc/reginfo.c b/gcc/reginfo.c
index 1510ce8..879f50b 100644
--- a/gcc/reginfo.c
+++ b/gcc/reginfo.c
@@ -495,10 +495,9 @@ init_reg_sets_1 (void)
       else if (i == ARG_POINTER_REGNUM && fixed_regs[i])
 	;
 #endif
-#ifndef PIC_OFFSET_TABLE_REG_CALL_CLOBBERED
-      else if (i == (unsigned) PIC_OFFSET_TABLE_REGNUM && fixed_regs[i])
+      else if (!PIC_OFFSET_TABLE_REG_CALL_CLOBBERED
+	       && i == (unsigned) PIC_OFFSET_TABLE_REGNUM && fixed_regs[i])
 	;
-#endif
       else if (CALL_REALLY_USED_REGNO_P (i))
         {
 	  SET_HARD_REG_BIT (regs_invalidated_by_call, i);
diff --git a/gcc/rtlanal.c b/gcc/rtlanal.c
index f9e6871..4331f41 100644
--- a/gcc/rtlanal.c
+++ b/gcc/rtlanal.c
@@ -118,13 +118,11 @@ rtx_unstable_p (const_rtx x)
 	  /* The arg pointer varies if it is not a fixed register.  */
 	  || (x == arg_pointer_rtx && fixed_regs[ARG_POINTER_REGNUM]))
 	return 0;
-#ifndef PIC_OFFSET_TABLE_REG_CALL_CLOBBERED
       /* ??? When call-clobbered, the value is stable modulo the restore
 	 that must happen after a call.  This currently screws up local-alloc
 	 into believing that the restore is not needed.  */
-      if (x == pic_offset_table_rtx)
+      if (!PIC_OFFSET_TABLE_REG_CALL_CLOBBERED && x == pic_offset_table_rtx)
 	return 0;
-#endif
       return 1;
 
     case ASM_OPERANDS:
@@ -197,14 +195,11 @@ rtx_varies_p (const_rtx x, bool for_alias)
 	  || (x == arg_pointer_rtx && fixed_regs[ARG_POINTER_REGNUM]))
 	return 0;
       if (x == pic_offset_table_rtx
-#ifdef PIC_OFFSET_TABLE_REG_CALL_CLOBBERED
 	  /* ??? When call-clobbered, the value is stable modulo the restore
 	     that must happen after a call.  This currently screws up
 	     local-alloc into believing that the restore is not needed, so we
 	     must return 0 only if we are called from alias analysis.  */
-	  && for_alias
-#endif
-	  )
+	  && (!PIC_OFFSET_TABLE_REG_CALL_CLOBBERED || for_alias))
 	return 0;
       return 1;