* expmed.c (extract_bit_field): Allow for the case of non-integer

        objects that are smaller than a word (like SFmode on a 64-bit
        machine).

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@30185 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5416ab4..24f2e3e 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -6,6 +6,10 @@ Tue Oct 26 00:41:54 1999  Bernd Schmidt  <bernds@cygnus.co.uk>
 
 Mon Oct 25 23:54:45 1999  Geoff Keating  <geoffk@cygnus.com>
 
+       * expmed.c (extract_bit_field): Allow for the case of non-integer
+       objects that are smaller than a word (like SFmode on a 64-bit
+       machine).
+
        * loop.c (basic_induction_var): A non-integer variable which is
        being set by a paradoxical subreg is probably not a biv.
 

diff --git a/gcc/expmed.c b/gcc/expmed.c
index 291d766..be458ce 100644 (file)
--- a/gcc/expmed.c
+++ b/gcc/expmed.c
@@ -963,6 +963,7 @@ extract_bit_field (str_rtx, bitsize, bitnum, unsignedp,
   register rtx op0 = str_rtx;
   rtx spec_target = target;
   rtx spec_target_subreg = 0;
+  enum machine_mode int_mode;
 #ifdef HAVE_extv
   int extv_bitsize;
   enum machine_mode extv_mode;
@@ -1168,10 +1169,19 @@ extract_bit_field (str_rtx, bitsize, bitnum, unsignedp,
                           NULL_RTX, 0);
     }
   
-  /* From here on we know the desired field is smaller than a word
-     so we can assume it is an integer.  So we can safely extract it as one
-     size of integer, if necessary, and then truncate or extend
-     to the size that is wanted.  */
+  /* From here on we know the desired field is smaller than a word.  */
+
+  /* Check if there is a correspondingly-sized integer field, so we can
+     safely extract it as one size of integer, if necessary; then
+     truncate or extend to the size that is wanted; then use SUBREGs or
+     convert_to_mode to get one of the modes we really wanted.  */
+  
+  int_mode = int_mode_for_mode (tmode);
+  if (int_mode == BLKmode)
+    int_mode = int_mode_for_mode (mode);
+  if (int_mode == BLKmode)
+    abort();    /* Should probably push op0 out to memory and then
+                  do a load.  */
 
   /* OFFSET is the number of words or bytes (UNIT says which)
      from STR_RTX to the first word or byte containing part of the field.  */
@@ -1326,15 +1336,15 @@ extract_bit_field (str_rtx, bitsize, bitnum, unsignedp,
          else
            {
              delete_insns_since (last);
-             target = extract_fixed_bit_field (tmode, op0, offset, bitsize,
+             target = extract_fixed_bit_field (int_mode, op0, offset, bitsize,
                                                bitpos, target, 1, align);
            }
        }
       else
         extzv_loses:
 #endif
-       target = extract_fixed_bit_field (tmode, op0, offset, bitsize, bitpos,
-                                         target, 1, align);
+      target = extract_fixed_bit_field (int_mode, op0, offset, bitsize, 
+                                       bitpos, target, 1, align);
     }
   else
     {
@@ -1462,15 +1472,15 @@ extract_bit_field (str_rtx, bitsize, bitnum, unsignedp,
          else
            {
              delete_insns_since (last);
-             target = extract_fixed_bit_field (tmode, op0, offset, bitsize,
+             target = extract_fixed_bit_field (int_mode, op0, offset, bitsize,
                                                bitpos, target, 0, align);
            }
        } 
       else
        extv_loses:
 #endif
-       target = extract_fixed_bit_field (tmode, op0, offset, bitsize, bitpos,
-                                         target, 0, align);
+      target = extract_fixed_bit_field (int_mode, op0, offset, bitsize, 
+                                       bitpos, target, 0, align);
     }
   if (target == spec_target)
     return target;