X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=OPTIMIZATIONS;h=6eed38079e71691fd84c2691b3d1d71a851e7f55;hb=cd13034f9415f64cdaa05893a4ac5ff1e95c97bd;hp=28068847ba715b735ebc6659da740fd0c7140322;hpb=043a8820506178134574627c2d7f07dc79070bd8;p=sbcl.git diff --git a/OPTIMIZATIONS b/OPTIMIZATIONS index 2806884..6eed380 100644 --- a/OPTIMIZATIONS +++ b/OPTIMIZATIONS @@ -90,25 +90,14 @@ VOP DATA-VECTOR-SET/SIMPLE-STRING V2!14[EDI] t32[EAX] t30[S2]>t33[CL] (incf x))))))) (format t "~A~%" x))) -------------------------------------------------------------------------------- -#7 -(defun foo (x) - (declare (optimize speed (debug 0))) - (if (< x 0) x (foo (1- x)))) - -SBCL generates a full call of FOO (but CMUCL does not). - -Partial explanation: CMUCL does generate a full (tail) call to FOO if -*BLOCK-COMPILE* is NIL. Maybe this is because in that case CMUCL doesn't -generate a temporary(?) function in its IR1-TRANSLATOR for %DEFUN? --------------------------------------------------------------------------------- #8 (defun foo (d) (declare (optimize (speed 3) (safety 0) (debug 0))) (declare (type (double-float 0d0 1d0) d)) (loop for i fixnum from 1 to 5 - for x1 double-float = (sin d) ;;; !!! - do (loop for j fixnum from 1 to 4 - sum x1 double-float))) + for x1 double-float = (sin d) ;;; !!! + do (loop for j fixnum from 1 to 4 + sum x1 double-float))) Without the marked declaration Python will use boxed representation for X1. @@ -162,3 +151,29 @@ tests lowtag. FAST-+/FIXNUM and similar should accept unboxed arguments in interests of representation selection. Problem: inter-TN dependencies. -------------------------------------------------------------------------------- +#14 +The derived type of (/ (THE (DOUBLE-FLOAT (0D0)) X) (THE (DOUBLE-FLOAT +1D0) Y)) is (DOUBLE-FLOAT 0.0d0). While it might be reasonable, it is +better to derive (OR (MEMBER 0.0d0) (DOUBLE-FLOAT (0.0d0))). +-------------------------------------------------------------------------------- +#15 +On the alpha, the system is reluctant to refer directly to a constant bignum, +preferring to load a large constant through a slow sequence of instructions, +then cons up a bignum for it: + +(LAMBDA (A) + (DECLARE (OPTIMIZE (SAFETY 1) (SPEED 3) (DEBUG 1)) + (TYPE (INTEGER -10000 10000) A) + (IGNORABLE A)) + (CASE A + ((89 125 16) (ASH A (MIN 18 -706))) + (T (DPB -3 (BYTE 30 30) -1)))) +-------------------------------------------------------------------------------- +#16 +(do ((i 0 (1+ i))) + ((= i (the (integer 0 100) n))) + ...) + +It is commonly expected for Python to derive (FIXNUMP I). (If ``='' is +replaced with ``>='', Python will do.) +--------------------------------------------------------------------------------