mirror/guile
mirror/guile
1
Fork 0
mirror of https://git.savannah.gnu.org/git/guile.git synced 2025-06-10 22:10:21 +02:00
Code Activity

Add stack size computation to disassembler

Browse source 
* module/system/vm/disassembler.scm (define-stack-effect-parser)
  (stack-effect-parsers, instruction-stack-size-after): New stack size
  facility.
  (define-clobber-parser, clobber-parsers, instruction-slot-clobbers):
  Take incoming and outgoing stack sizes as arguments to interpret
  SP-relative clobbers.

* module/system/vm/frame.scm (compute-frame-sizes): New helper that
  computes frame sizes for each position in a function.
  (compute-killv): Adapt to compute the clobbered set given the computed
  frame sizes.
This commit is contained in:
Andy Wingo 2015-10-21 15:02:28 +02:00
parent 4afb46f859
commit f03960412e
2 changed files with 121 additions and 11 deletions
Download patch file Download diff file Expand all files Collapse all files

78
module/system/vm/disassembler.scm
View file

@ -39,6 +39,7 @@
instruction-length
instruction-has-fallthrough?
instruction-relative-jump-targets
instruction-stack-size-after
instruction-slot-clobbers))
(define-syntax-rule (u32-ref buf n)
@ -536,15 +537,70 @@ address of that offset."
(let ((opcode (logand (bytevector-u32-native-ref code pos) #xff)))
((vector-ref jump-parsers opcode) code pos)))
(define-syntax define-stack-effect-parser
(lambda (x)
(define (stack-effect-parser name)
(case name
((push)
#'(lambda (code pos size) (+ size 1)))
((pop)
#'(lambda (code pos size) (- size 1)))
((drop)
#'(lambda (code pos size)
(let ((count (ash (bytevector-u32-native-ref code pos) -8)))
(- size count))))
((alloc-frame reset-frame)
#'(lambda (code pos size)
(let ((nlocals (ash (bytevector-u32-native-ref code pos) -8)))
nlocals)))
((receive)
#'(lambda (code pos size)
(let ((nlocals (ash (bytevector-u32-native-ref code (+ pos 4))
-8)))
nlocals)))
((bind-kwargs)
#'(lambda (code pos size)
(let ((ntotal (ash (bytevector-u32-native-ref code (+ pos 8)) -8)))
ntotal)))
((bind-rest)
#'(lambda (code pos size)
(let ((dst (ash (bytevector-u32-native-ref code pos) -8)))
(+ dst 1))))
((assert-nargs-ee/locals)
#'(lambda (code pos size)
(let ((nargs (logand (ash (bytevector-u32-native-ref code pos) -8)
#xfff))
(nlocals (ash (bytevector-u32-native-ref code pos) -20)))
(+ nargs nlocals))))
((call call-label)
#'(lambda (code pos size) #f))
((tail-call tail-call-label tail-call/shuffle tail-apply)
#'(lambda (code pos size) #f))
(else
#f)))
(syntax-case x ()
((_ name opcode kind word0 word* ...)
(let ((parser (stack-effect-parser (syntax->datum #'name))))
(if parser
#`(vector-set! stack-effect-parsers opcode #,parser)
#'(begin)))))))
(define stack-effect-parsers (make-vector 256 (lambda (code pos size) size)))
(visit-opcodes define-stack-effect-parser)
(define (instruction-stack-size-after code pos size)
(let ((opcode (logand (bytevector-u32-native-ref code pos) #xff)))
((vector-ref stack-effect-parsers opcode) code pos size)))
(define-syntax define-clobber-parser
(lambda (x)
(syntax-case x ()
((_ name opcode kind arg ...)
((_ name opcode kind arg0 arg* ...)
(case (syntax->datum #'kind)
((!)
(case (syntax->datum #'name)
((call call-label)
#'(let ((parse (lambda (code pos nslots)
#'(let ((parse (lambda (code pos nslots-in nslots-out)
(call-with-values
(lambda ()
(disassemble-one code (/ pos 4)))
@ -552,26 +608,32 @@ address of that offset."
(match elt
((_ proc . _)
(let lp ((slot (- proc 2)))
(if (< slot nslots)
(if (< slot nslots-in)
(cons slot (lp (1+ slot)))
'())))))))))
(vector-set! clobber-parsers opcode parse)))
(else
#'(begin))))
((<-)
#'(let ((parse (lambda (code pos nslots)
#`(let ((parse (lambda (code pos nslots-in nslots-out)
(call-with-values
(lambda ()
(disassemble-one code (/ pos 4)))
(lambda (len elt)
(match elt
((_ dst . _) (list dst))))))))
((_ dst . _)
#,(case (syntax->datum #'arg0)
((X8_F24 X8_F12_F12)
#'(list dst))
(else
#'(list (- nslots-out 1 dst)))))))))))
(vector-set! clobber-parsers opcode parse)))
(else (error "unexpected instruction kind" #'kind)))))))
(define clobber-parsers (make-vector 256 (lambda (code pos nslots) '())))
(define clobber-parsers
(make-vector 256 (lambda (code pos nslots-in nslots-out) '())))
(visit-opcodes define-clobber-parser)
(define (instruction-slot-clobbers code pos nslots)
(define (instruction-slot-clobbers code pos nslots-in nslots-out)
(let ((opcode (logand (bytevector-u32-native-ref code pos) #xff)))
((vector-ref clobber-parsers opcode) code pos nslots)))
((vector-ref clobber-parsers opcode) code pos nslots-in nslots-out)))

54
module/system/vm/frame.scm
View file

@ -25,6 +25,7 @@
#:use-module (system vm debug)
#:use-module (system vm disassembler)
#:use-module (srfi srfi-9)
#:use-module (srfi srfi-11)
#:use-module (rnrs bytevectors)
#:use-module (ice-9 match)
#:export (binding-index
@ -83,6 +84,49 @@
(lp (1+ n) (+ pos (vector-ref parsed n)))))
preds))
(define (compute-frame-sizes code parsed initial-size)
(let ((in-sizes (make-vector (vector-length parsed) #f))
(out-sizes (make-vector (vector-length parsed) #f)))
;; This only computes all possible valid stack sizes if the bytecode
;; is sorted topologically. Guiles' compiler does this currently,
;; but if that changes we should do a proper pre-order visit. Of
;; course the bytecode has to be valid too.
(define (find-idx n diff)
(let lp ((n n) (diff diff))
(cond
((negative? diff)
(lp (1- n) (+ diff (vector-ref parsed (1- n)))))
((positive? diff)
(lp (1+ n) (- diff (vector-ref parsed n))))
(else n))))
(vector-set! in-sizes 0 initial-size)
(let lp ((n 0) (pos 0))
(define (offset->idx target)
(call-with-values (lambda ()
(if (>= target pos)
(values n pos)
(values 0 0)))
(lambda (n pos)
(let lp ((n n) (pos pos))
(cond
((= pos target) n)
((< pos target) (lp (1+ n) (+ pos (vector-ref parsed n))))
(else (error "bad target" target)))))))
(when (< n (vector-length parsed))
(let* ((in (vector-ref in-sizes n))
(out (instruction-stack-size-after code pos in)))
(vector-set! out-sizes n out)
(when out
(when (instruction-has-fallthrough? code pos)
(vector-set! in-sizes (1+ n) out))
(for-each (lambda (target)
(let ((idx (find-idx n target)))
(when idx
(vector-set! in-sizes idx out))))
(instruction-relative-jump-targets code pos))))
(lp (1+ n) (+ pos (vector-ref parsed n)))))
(values in-sizes out-sizes)))
(define (compute-genv parsed defs)
(let ((genv (make-vector (vector-length parsed) '())))
(define (add-def! pos var)
@ -118,8 +162,11 @@
by-slot))
(define (compute-killv code parsed defs)
(let ((defs-by-slot (compute-defs-by-slot defs))
(killv (make-vector (vector-length parsed) #f)))
(let*-values (((defs-by-slot) (compute-defs-by-slot defs))
((initial-frame-size) (vector-length defs-by-slot))
((in-sizes out-sizes)
(compute-frame-sizes code parsed initial-frame-size))
((killv) (make-vector (vector-length parsed) #f)))
(define (kill-slot! n slot)
(bit-set*! (vector-ref killv n) (vector-ref defs-by-slot slot) #t))
(let lp ((n 0))
@ -147,7 +194,8 @@
(when (< slot (vector-length defs-by-slot))
(kill-slot! n slot)))
(instruction-slot-clobbers code pos
(vector-length defs-by-slot)))
(vector-ref in-sizes n)
(vector-ref out-sizes n)))
(lp (1+ n) (+ pos (vector-ref parsed n)))))
killv))