-;;;; type testing and checking VOPs for the x86 VM
+;;;; type testing and checking VOPs for the x86-64 VM
;;;; This software is part of the SBCL system. See the README file for
;;;; more information.
\f
;;;; test generation utilities
-(defun make-byte-tn (tn)
- (aver (sc-is tn any-reg descriptor-reg unsigned-reg signed-reg))
- (make-random-tn :kind :normal
- :sc (sc-or-lose 'byte-reg)
- :offset (tn-offset tn)))
-
(defun generate-fixnum-test (value)
"zero flag set if VALUE is fixnum"
- (let ((offset (tn-offset value)))
- ;; The x86 backend uses a pun from E[A-D]X -> [A-D]L for these
- ;; tests. The Athlon 64 optimization guide says that this is a
- ;; bad idea, so it's been removed.
- (cond ((sc-is value control-stack)
- (inst test (make-ea :byte :base rbp-tn
- :disp (- (* (1+ offset) n-word-bytes)))
- sb!vm::fixnum-tag-mask))
- (t
- (inst test value sb!vm::fixnum-tag-mask)))))
+ (inst test
+ (cond ((sc-is value any-reg descriptor-reg)
+ (make-byte-tn value))
+ ((sc-is value control-stack)
+ (make-ea :byte :base rbp-tn
+ :disp (- (* (1+ (tn-offset value)) n-word-bytes))))
+ (t
+ value))
+ sb!vm::fixnum-tag-mask))
(defun %test-fixnum (value target not-p)
(generate-fixnum-test value)
(%test-headers value target not-p nil headers drop-through))
(defun %test-lowtag (value target not-p lowtag)
- (move rax-tn value)
- (inst and rax-tn lowtag-mask)
- (inst cmp rax-tn lowtag)
+ (if (and (sc-is value any-reg descriptor-reg)
+ (< (tn-offset value) r8-offset))
+ (move eax-tn (make-dword-tn value)) ; shorter encoding (no REX prefix)
+ (move rax-tn value))
+ (inst and al-tn lowtag-mask)
+ (inst cmp al-tn lowtag)
(inst jmp (if not-p :ne :e) target))
(defun %test-headers (value target not-p function-p headers