2008-03-11 Basile Starynkevitch <basile@starynkevitch.net>

	merged with trunk r133107



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/melt-branch@133113 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 32 insertions, 9 deletions

diff --git a/gcc/df.h b/gcc/df.h
index 7c14f163dc0..cf113aefd50 100644
--- a/gcc/df.h
+++ b/gcc/df.h
@@ -117,14 +117,18 @@ enum df_ref_flags
     DF_REF_MUST_CLOBBER = 1 << 7,
 
 
-    /* This flag is set if this ref is inside a pre/post modify.  */
-    DF_REF_PRE_POST_MODIFY = 1 << 8,
+    /* If the ref has one of the following two flags set, then the
+       struct df_ref can be cast to struct df_ref_extract to access
+       the width and offset fields.  */
+ 
+    /* This flag is set if the ref contains a SIGN_EXTRACT.  */
+    DF_REF_SIGN_EXTRACT = 1 << 8,
 
-    /* This flag is set if the ref contains a ZERO_EXTRACT or SIGN_EXTRACT.  */
-    DF_REF_EXTRACT = 1 << 9,
+    /* This flag is set if the ref contains a ZERO_EXTRACT.  */
+    DF_REF_ZERO_EXTRACT = 1 << 9,
 
-    /* This flag is set if the ref contains a STRICT_LOWER_PART.  */
-    DF_REF_STRICT_LOWER_PART = 1 << 10,
+    /* This flag is set if the ref contains a STRICT_LOW_PART.  */
+    DF_REF_STRICT_LOW_PART = 1 << 10,
 
     /* This flag is set if the ref contains a SUBREG.  */
     DF_REF_SUBREG = 1 << 11,
@@ -138,7 +142,11 @@ enum df_ref_flags
     DF_REF_CALL_STACK_USAGE = 1 << 13,
 
     /* This flag is used for verification of existing refs. */
-    DF_REF_REG_MARKER = 1 << 14
+    DF_REF_REG_MARKER = 1 << 14,
+
+    /* This flag is set if this ref is inside a pre/post modify.  */
+    DF_REF_PRE_POST_MODIFY = 1 << 15
+
   };
 
 /* The possible ordering of refs within the df_ref_info.  */
@@ -381,6 +389,17 @@ struct df_ref
   struct df_ref *prev_reg;     /* Prev ref with same regno and type.  */
 };
 
+/* A df_ref_extract is just a df_ref with a width and offset field at
+   the end of it.  It is used to hold this information if the ref was
+   wrapped by a SIGN_EXTRACT or a ZERO_EXTRACT and to pass this info
+   to passes that wish to process partial regs precisely.  */
+struct df_ref_extract
+{
+  struct df_ref ref;
+  int width;
+  int offset;
+};
+
 /* These links are used for two purposes:
    1) def-use or use-def chains. 
    2) Multiword hard registers that underly a single hardware register.  */
@@ -598,7 +617,10 @@ struct df
 #define DF_REF_IS_REG_MARKED(REF) (DF_REF_FLAGS_IS_SET ((REF),DF_REF_REG_MARKER))
 #define DF_REF_NEXT_REG(REF) ((REF)->next_reg)
 #define DF_REF_PREV_REG(REF) ((REF)->prev_reg)
-
+/* The following two macros may only be applied if one of 
+   DF_REF_SIGN_EXTRACT | DF_REF_ZERO_EXTRACT is true. */ 
+#define DF_REF_WIDTH(REF) (((struct df_ref_extract *)(REF))->width)
+#define DF_REF_OFFSET(REF) (((struct df_ref_extract *)(REF))->offset)
 /* Macros to determine the reference type.  */
 
 #define DF_REF_REG_DEF_P(REF) (DF_REF_TYPE (REF) == DF_REF_REG_DEF)
@@ -862,7 +884,8 @@ extern void df_grow_reg_info (void);
 extern void df_grow_insn_info (void);
 extern void df_scan_blocks (void);
 extern struct df_ref *df_ref_create (rtx, rtx *, rtx,basic_block, 
-				     enum df_ref_type, enum df_ref_flags);
+				     enum df_ref_type, enum df_ref_flags,
+				     int, int);
 extern void df_ref_remove (struct df_ref *);
 extern struct df_insn_info * df_insn_create_insn_record (rtx);
 extern void df_insn_delete (basic_block, unsigned int);