New function: SB!KERNEL:%MULTIPLY-HIGH

[sbcl.git] / src / compiler / x86-64 / arith.lisp

diff --git a/src/compiler/x86-64/arith.lisp b/src/compiler/x86-64/arith.lisp
index cfe4ad4..cd06c8e 100644 (file)
--- a/src/compiler/x86-64/arith.lisp
+++ b/src/compiler/x86-64/arith.lisp
@@ -667,6 +667,8 @@
                                        (location= number result)))))
   (:result-types tagged-num)
   (:note "inline ASH")
+  (:variant nil)
+  (:variant-vars modularp)
   (:generator 2
     (cond ((and (= amount 1) (not (location= number result)))
            (inst lea result (make-ea :qword :base number :index number)))
@@ -685,8 +687,11 @@
                         (inst sar result (- amount))
                         (inst and result (lognot fixnum-tag-mask)))))
                  ((plusp amount)
+                  (unless modularp
+                    (aver (not "Impossible: fixnum ASH should not be called with
+constant shift greater than word length")))
                   (if (sc-is result any-reg)
-                      (inst xor result result)
+                      (zeroize result)
                       (inst mov result 0)))
                  (t (inst sar result 63)
                     (inst and result (lognot fixnum-tag-mask))))))))
@@ -1367,6 +1372,7 @@
 
 (define-vop (fast-ash-left-smod61-c/fixnum=>fixnum
              fast-ash-c/fixnum=>fixnum)
+  (:variant :modular)
   (:translate ash-left-smod61))
 (define-vop (fast-ash-left-smod61/fixnum=>fixnum
              fast-ash-left/fixnum=>fixnum))
@@ -1604,6 +1610,42 @@
     (move hi edx)
     (move lo eax)))
 
+#!+multiply-high-vops
+(define-vop (mulhi)
+  (:translate sb!kernel:%multiply-high)
+  (:policy :fast-safe)
+  (:args (x :scs (unsigned-reg) :target eax)
+         (y :scs (unsigned-reg unsigned-stack)))
+  (:arg-types unsigned-num unsigned-num)
+  (:temporary (:sc unsigned-reg :offset eax-offset :from (:argument 0))
+              eax)
+  (:temporary (:sc unsigned-reg :offset edx-offset :from (:argument 1)
+                   :to (:result 0) :target hi) edx)
+  (:results (hi :scs (unsigned-reg)))
+  (:result-types unsigned-num)
+  (:generator 20
+    (move eax x)
+    (inst mul eax y)
+    (move hi edx)))
+
+#!+multiply-high-vops
+(define-vop (mulhi/fx)
+  (:translate sb!kernel:%multiply-high)
+  (:policy :fast-safe)
+  (:args (x :scs (any-reg) :target eax)
+         (y :scs (unsigned-reg unsigned-stack)))
+  (:arg-types positive-fixnum unsigned-num)
+  (:temporary (:sc any-reg :offset eax-offset :from (:argument 0)) eax)
+  (:temporary (:sc any-reg :offset edx-offset :from (:argument 1)
+                   :to (:result 0) :target hi) edx)
+  (:results (hi :scs (any-reg)))
+  (:result-types positive-fixnum)
+  (:generator 15
+    (move eax x)
+    (inst mul eax y)
+    (move hi edx)
+    (inst and hi (lognot fixnum-tag-mask))))
+
 (define-vop (bignum-lognot lognot-mod64/unsigned=>unsigned)
   (:translate sb!bignum:%lognot))
 
@@ -1622,7 +1664,7 @@
     (inst sar digit 3)))
 
 (define-vop (bignum-floor)
-  (:translate sb!bignum:%floor)
+  (:translate sb!bignum:%bigfloor)
   (:policy :fast-safe)
   (:args (div-high :scs (unsigned-reg) :target edx)
          (div-low :scs (unsigned-reg) :target eax)