Changeset 5588 for trunk/ccl/level-0/X86/X8664

Timestamp:

Dec 4, 2006, 7:46:36 PM (14 years ago)

Author:

gb

Message:

Ensure that %ASHL handles shift count of 32 (and returns 0 in that case.)

File:

• trunk/ccl/level-0/X86/X8664/x8664-bignum.lisp (modified) (5 diffs)

trunk/ccl/level-0/X86/X8664/x8664-bignum.lisp

@@ -97 +97 @@
 ;;; resulting from dividing hi:low by divisor.
 ;;; We only have two immediate registers, and -have- to use them
-;;; to represent hi:low.  We -can- store the unboxed divisor in
-;;; %ebp, if we commit to the idea that %rbp will never be traced
-;;; by the GC.  I'm willing to commit to that for x8664, since
-;;; this is an example of not having enough imm regs.  We do need
-;;; to save/restore %rbp, but hopefully we can do wo without
-;;; hitting memory.
+;;; to represent hi:low.  Keep the unboxed divisor in the high
+;;; word of a fixnum on the top of the stack.  (That's probably
+;;; slower than using %rbp, but clobbering %rbp confuses backtrace).
 ;;; For x8632, we'll probably have to mark something (%ecx ?) as
 ;;; being "temporarily unboxed" by mucking with some bits in the
@@ -109 +106 @@
   (let ((unboxed-high imm1)
         (unboxed-low imm0)
-        (unboxed-divisor ebp)
         (unboxed-quo imm0)
         (unboxed-rem imm1))
-    (movd (% rbp) (% mm0))
-    (unbox-fixnum divisor rbp)
+    (unbox-fixnum divisor imm0)
+    (pushq ($ 0))
+    (movl (%l imm0) (@ 4 (% rsp)))
     (unbox-fixnum num-high unboxed-high)
     (unbox-fixnum num-low unboxed-low)
-    (divl (% ebp))
-    (movd (% mm0) (% rbp))
+    (divl (@ 4 (% rsp)))
+    (addq ($ 8) (% rsp))
     (box-fixnum unboxed-quo arg_y)
     (box-fixnum unboxed-rem arg_z)
@@ -205 +202 @@
 ;;; Again, we're out of imm regs: a variable shift count has to go in %cl.
 ;;; Make sure that the rest of %rcx is 0, to keep the GC happy.
-;;; %rcx == temp1
+;;; %rcx == temp2
 (defx86lapfunction %digit-logical-shift-right ((digit arg_y) (count arg_z))
   (unbox-fixnum digit imm0)
@@ -215 +212 @@
   (box-fixnum imm0 arg_z)
   (single-value-return))
+
+
 
 (defx86lapfunction %ashr ((digit arg_y) (count arg_z))
@@ -232 +231 @@
   (xorq (% temp2) (% temp2))
   (movb (% imm1.b) (% temp2.b))
-  (shll (% temp2.b) (%l imm0))
+  (shlq (% temp2.b) (% imm0))
   (movb ($ 0) (% temp2.b))  
   (movl (%l imm0) (%l imm0))            ;zero-extend