* ifield.scm (<ifield> 'field-start): Don't look at word-len.

diff --git a/cgen/ChangeLog b/cgen/ChangeLog
index a676b15..926e7b9 100644 (file)
--- a/cgen/ChangeLog
+++ b/cgen/ChangeLog
@@ -1,3 +1,7 @@
+2001-07-09  Geoffrey Keating  <geoffk@redhat.com>
+
+       * ifield.scm (<ifield> 'field-start): Don't look at word-len.
+
 2001-07-06  Ben Elliston  <bje@redhat.com>
 
        * opcodes.scm (read-cpu.opc): Read .opc files from subdir/cpu.

diff --git a/cgen/ifield.scm b/cgen/ifield.scm
index 82db538..9c8f97e 100644 (file)
--- a/cgen/ifield.scm
+++ b/cgen/ifield.scm
@@ -91,42 +91,11 @@
 (define (ifld-decode-mode f) (ifld-mode f))
 
 ; Return start of ifield.
-; WORD-LEN is the length of the word in which to compute the value or
-; #f meaning to use the default length (recorded with the bitrange).
-; WORD-LEN is present for architectures like the m32r where there are insns
-; smaller than the base insn size (LIW).
-; ??? Not sure it'll be applicable to other LIW architectures.  The m32r is
-; rather easy as the insns are 16 and 32 bits.
-; ??? Another way to do this would be to either set the base-insn-size for
-; the m32r to be 16 bits, or to add a new field to hold the insn-word-size
-; and set it to 16 for the m32r.  The problem here is that there is no
-; canonicalization that works regardless of whether a "word" is shortened
-; or lengthened.
 
 (method-make-virtual!
  <ifield> 'field-start
  (lambda (self word-len)
-   (let* ((bitrange (-ifld-bitrange self))
-         (lsb0? (bitrange-lsb0? bitrange))
-         (recorded-word-len (bitrange-word-length bitrange))
-         (wanted-word-len (or word-len recorded-word-len)))
-     ; Note that this is only intended for situations like the m32r.
-     ; If it doesn't work elsewhere, it may be that you need to
-     ; do things different (use two fields instead of one).
-     (cond ((= wanted-word-len recorded-word-len)
-           (bitrange-start bitrange))
-          ((< wanted-word-len recorded-word-len)
-           ; smaller word wanted
-           (if lsb0?
-               (- (bitrange-start bitrange) (- recorded-word-len
-                                               wanted-word-len))
-               (bitrange-start bitrange)))
-          (else
-           ; larger word wanted
-           (if lsb0?
-               (+ (bitrange-start bitrange) (- wanted-word-len
-                                               recorded-word-len))
-               (bitrange-start bitrange))))))
+   (bitrange-start (-ifld-bitrange self)))
 )
 
 (define (ifld-start ifld word-len)