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-rw-r--r--module/system/vm/assembler.scm65
1 files changed, 63 insertions, 2 deletions
diff --git a/module/system/vm/assembler.scm b/module/system/vm/assembler.scm
index 51777287f..556f58920 100644
--- a/module/system/vm/assembler.scm
+++ b/module/system/vm/assembler.scm
@@ -1411,8 +1411,69 @@ it will be added to the GC roots at runtime."
(linker-object-section strtab)))
strtab))))
+;;;
+;;; The .guile.procprops section is a packed, sorted array of (pc, addr)
+;;; values. Pc and addr are both 32 bits wide. (Either could change to
+;;; 64 bits if appropriate in the future.) Pc is the address of the
+;;; entry to a program, relative to the start of the text section, and
+;;; addr is the address of the associated properties alist, relative to
+;;; the start of the ELF image.
+;;;
+;;; Since procedure properties are stored in the data sections, we need
+;;; to link the procedures property section first. (Note that this
+;;; constraint does not apply to the arities section, which may
+;;; reference the data sections via the kw-indices literal, because
+;;; assembling the text section already makes sure that the kw-indices
+;;; are interned.)
+;;;
+
+;; The size of a procprops entry, in bytes.
+(define procprops-size 8)
+
+(define (link-procprops asm)
+ (define (assoc-remove-one alist key value-pred)
+ (match alist
+ (() '())
+ ((((? (lambda (x) (eq? x key))) . value) . alist)
+ (if (value-pred value)
+ alist
+ (acons key value alist)))
+ (((k . v) . alist)
+ (acons k v (assoc-remove-one alist key value-pred)))))
+ (define (props-without-name-or-docstring meta)
+ (assoc-remove-one
+ (assoc-remove-one (meta-properties meta) 'name (lambda (x) #t))
+ 'documentation
+ string?))
+ (define (find-procprops)
+ (filter-map (lambda (meta)
+ (let ((props (props-without-name-or-docstring meta)))
+ (and (pair? props)
+ (cons (meta-low-pc meta) props))))
+ (reverse (asm-meta asm))))
+ (let* ((endianness (asm-endianness asm))
+ (procprops (find-procprops))
+ (bv (make-bytevector (* (length procprops) procprops-size) 0)))
+ (let lp ((procprops procprops) (pos 0) (relocs '()))
+ (match procprops
+ (()
+ (make-object asm '.guile.procprops
+ bv
+ relocs '()
+ #:type SHT_PROGBITS #:flags 0))
+ (((pc . props) . procprops)
+ (bytevector-u32-set! bv pos pc endianness)
+ (lp procprops
+ (+ pos procprops-size)
+ (cons (make-linker-reloc 'abs32/1 (+ pos 4) 0
+ (intern-constant asm props))
+ relocs)))))))
+
(define (link-objects asm)
- (let*-values (((ro rw rw-init) (link-constants asm))
+ (let*-values (;; Link procprops before constants, because it probably
+ ;; interns more constants.
+ ((procprops) (link-procprops asm))
+ ((ro rw rw-init) (link-constants asm))
;; Link text object after constants, so that the
;; constants initializer gets included.
((text) (link-text-object asm))
@@ -1425,7 +1486,7 @@ it will be added to the GC roots at runtime."
((shstrtab) (link-shstrtab asm)))
(filter identity
(list text ro rw dt symtab strtab arities arities-strtab
- docstrs docstrs-strtab shstrtab))))
+ docstrs docstrs-strtab procprops shstrtab))))