Raymond Toy pushed to branch rtoy-amd64-p1 at cmucl / cmucl

Commits:

• 4f8e35c9
  by Raymond Toy at 2020-08-15T10:36:10-07:00

  emit-ea needs to support float-registers
  
  emit-ea with a tn arg needs to recognize a float-register.  The x86
  port does this so we just copied it over.
  

• b626b6ff
  by Raymond Toy at 2020-08-16T12:14:13-07:00

  Allow using R12 in emit-ea
  
  Currently R12 is not allowed as an index register (a carry over from
  x86 because R12 is ESP when looking at the low 3 bits of the
  register).  However, if we emit the appropriate REX prefix, then I
  think R12 is ok to use here.  Just assume REX was emitted and allow
  use of R12 for now.
  

1 changed file:

• src/compiler/amd64/insts.lisp

Changes:

   (etypecase thing

     (tn

      (ecase (sb-name (sc-sb (tn-sc thing)))

-       (registers

+       ((registers float-registers)

 	(emit-mod-reg-r/m-byte segment #b11 reg (reg-lower-3-bits thing)))

        (stack

 	;; Convert stack tns into an index off of RBP.

 	 (let ((ss (1- (integer-length scale)))

 	       (index (if (null index)

 			  #b100

+			  ;; FIXME: We're going to assume this is ok

+			  ;; for now because we emitted an appropriate

+			  ;; REX prefix already to allow using R12

+			  ;; here.

+			  #+nil

 			  (if (= (reg-tn-encoding index) #b100)

 			      (error "Can't index off of RSP")

-			      (reg-lower-3-bits index))))

+			      (reg-lower-3-bits index))

+			  (reg-lower-3-bits index)))

 	       (base (if (null base)

 			 #b101

 			 (reg-lower-3-bits base))))