X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fassembly%2Fx86-64%2Falloc.lisp;h=80d5406329a8ba75ebdb934b86a6549ee1d356b2;hb=6147892310586401bae00de7e65a386c72531136;hp=a27364f935b7437147a127fb13f1ab43fe8dfc8f;hpb=8146eeb8708fbc225169707a49b32e9e977d546e;p=sbcl.git

diff --git a/src/assembly/x86-64/alloc.lisp b/src/assembly/x86-64/alloc.lisp
index a27364f..80d5406 100644
--- a/src/assembly/x86-64/alloc.lisp
+++ b/src/assembly/x86-64/alloc.lisp
@@ -70,3 +70,68 @@
   (def r13)
   (def r14)
   (def r15))
+
+#+sb-assembling
+(macrolet
+    ((def (reg)
+       (declare (ignorable reg))
+       #!+sb-thread
+       (let* ((name (intern (format nil "ALLOC-TLS-INDEX-IN-~A" reg)))
+              (target-offset (intern (format nil "~A-OFFSET" reg)))
+              (other-offset (if (eql 'rax reg)
+                                'rcx-offset
+                                'rax-offset)))
+         ;; Symbol starts in TARGET, where the TLS-INDEX ends up in.
+         `(define-assembly-routine ,name
+              ((:temp other descriptor-reg ,other-offset)
+               (:temp target descriptor-reg ,target-offset))
+            (let ((get-tls-index-lock (gen-label))
+                  (release-tls-index-lock (gen-label)))
+              (pseudo-atomic
+               ;; Save OTHER & push the symbol. RAX is either one of the two.
+               (inst push other)
+               (inst push target)
+               (emit-label get-tls-index-lock)
+               (inst mov target 1)
+               (zeroize rax-tn)
+               (inst cmpxchg (make-ea-for-symbol-value *tls-index-lock*)
+                     target :lock)
+               (inst jmp :ne get-tls-index-lock)
+               ;; The symbol is now in OTHER.
+               (inst pop other)
+               ;; Now with the lock held, see if the symbol's tls index has been
+               ;; set in the meantime.
+               (loadw target other symbol-tls-index-slot other-pointer-lowtag)
+               (inst or target target)
+               (inst jmp :ne release-tls-index-lock)
+               ;; Allocate a new tls-index.
+               (load-symbol-value target *free-tls-index*)
+               (let ((not-error (gen-label))
+                     (error (generate-error-code nil 'tls-exhausted-error)))
+                 (inst cmp target (fixnumize tls-size))
+                 (inst jmp :l not-error)
+                 (%clear-pseudo-atomic)
+                 (inst jmp error)
+                 (emit-label not-error))
+               (inst add (make-ea-for-symbol-value *free-tls-index*)
+                     (fixnumize 1))
+               (storew target other symbol-tls-index-slot other-pointer-lowtag)
+               (emit-label release-tls-index-lock)
+               ;; No need for barriers on x86/x86-64 on unlock.
+               (store-symbol-value 0 *tls-index-lock*)
+               ;; Restore OTHER.
+               (inst pop other))
+              (inst ret))))))
+  (def rax)
+  (def rcx)
+  (def rdx)
+  (def rbx)
+  (def rsi)
+  (def rdi)
+  (def r8)
+  (def r9)
+  (def r10)
+  (def r12)
+  (def r13)
+  (def r14)
+  (def r15))