|
|
;---------------------------Module-Header------------------------------;; Module Name: unroll.inc;; Equates and macros for loop unrolling.;; Copyright (c) 1992 Microsoft Corporation;-----------------------------------------------------------------------;
; Module including this must define LOOP_UNROLL_SHIFT. the log2 of the number; of times you want loops in this module unrolled. For example,; LOOP_UNROLL_SHIFT of 3 yields 2**3 = 8 times unrolling. This is the only; thing you need to change to control unrolling.
; # of times to unroll the loop, calculated as 2**n, where n is the; user-specified log2 of # of times to unroll the loop.
LOOP_UNROLL_COUNT equ (1 shl LOOP_UNROLL_SHIFT)
;-----------------------------------------------------------------------;; Macro to generate an unrolled loop of UNROLL_COUNT instances of BASE_MACRO,; passing the base macro the info needed to construct a label of the form; BASE_LABELxxx, where xxx is UNROLL_COUNT the first time, and counts down by; one each time thereafter.
UNROLL_LOOP macro BASE_MACRO,BASE_LABEL,UNROLL_COUNT
INDEX=UNROLL_COUNT rept UNROLL_COUNT ;-------------------------; &BASE_MACRO &BASE_LABEL,%INDEXINDEX=INDEX-1 endm ;-----------------------------------;
endm ;-----------------------------------;
;-----------------------------------------------------------------------;; Macro to generate a dword memory variable that points to the label; specified by concatenating the label and the index.
DEFINE_DD macro BASE_LABEL,INDEX ;------------------; dd &BASE_LABEL&INDEX endm ;-----------------------------------; ;-----------------------------------------------------------------------;; Macro to generate a table of vectors into an unrolled loop, for entering; to handle all possible fractional loops.
UNROLL_LOOP_ENTRY_TABLE macro TABLE,BASE_LABEL,UNROLL_COUNT align 4TABLE label dword DEFINE_DD BASE_LABEL,%&UNROLL_COUNT
INDEX=1 rept UNROLL_COUNT-1 DEFINE_DD BASE_LABEL,%INDEXINDEX=INDEX+1 endm ;-----------------------------------;
endm ;-----------------------------------;
;-----------------------------------------------------------------------;; Given a loop count, a vector table, and unrolling parameters, this generates; COUNT_DEST = # of times to execute unrolled loop, VEC_DEST = entry point into; unrolled loop to perform whatever fractional loop is needed. Assumes dests; are registers. SET_UP_UNROLL_VARS macro COUNT_DEST,VEC_DEST,COUNT_SOURCE,VEC_TABLE,UNROLL_SHIFT mov &VEC_DEST&,&COUNT_SOURCE& ;copy count to vector dest to ; work with it ifdifi <&COUNT_SOURCE&>,<&COUNT_DEST&> mov &COUNT_DEST&,&COUNT_SOURCE& ;copy to count dest too, if not endif ; same as count source add &COUNT_DEST&,(1 shl LOOP_UNROLL_SHIFT)-1 ;round count up and &VEC_DEST&,(1 shl LOOP_UNROLL_SHIFT)-1 ;fractional part of unrolled loop shr &COUNT_DEST&,UNROLL_SHIFT ;# of repetitions of unrolled loop mov &VEC_DEST&,&VEC_TABLE&[&VEC_DEST&*4] ;place to jump into the unrolled ; loop so as to handle the ; fractional part first endm ;-----------------------------------;
;-----------------------------------------------------------------------;; Given a loop count, a vector table, and unrolling parameters, this generates; COUNT_DEST = # of times to execute unrolled loop, VEC_DEST = entry point into; unrolled loop to perform whatever fractional loop is needed. Assumes dests; are registers. SET_UP_UNROLL_AND_BRANCH macro COUNT_REG,VEC_REG,VEC_TABLE,UNROLL_SHIFT mov &VEC_REG&,&COUNT_REG& ;copy count to vector dest to ; work with it add &COUNT_reg&,(1 shl LOOP_UNROLL_SHIFT)-1 ;round count up and &VEC_REG&,(1 shl LOOP_UNROLL_SHIFT)-1 ;fractional part of unrolled loop shr &COUNT_REG&,UNROLL_SHIFT ;# of repetitions of unrolled loop jmp dword ptr &VEC_TABLE&[&VEC_REG&*4] ;jump into the unrolled loop so as ; to handle the fractional part ; first endm ;-----------------------------------;
;-----------------------------------------------------------------------;
|
