- (sb!alien:with-alien
- ((lisp-interrupt-contexts (array (* os-context-t) nil) :extern))
- (let ((scp (sb!alien:deref lisp-interrupt-contexts index)))
- (when (= (sap-int frame-pointer)
- (sb!vm:context-register scp sb!vm::cfp-offset))
- (without-gcing
- (let ((code (code-object-from-bits
- (sb!vm:context-register scp sb!vm::code-offset))))
- (when (symbolp code)
- (return (values code 0 scp)))
- (let* ((code-header-len (* (get-header-data code)
- sb!vm:n-word-bytes))
- (pc-offset
- (- (sap-int (sb!vm:context-pc scp))
- (- (get-lisp-obj-address code)
- sb!vm:other-pointer-lowtag)
- code-header-len)))
- ;; Check to see whether we were executing in a branch
- ;; delay slot.
- #!+(or pmax sgi) ; pmax only (and broken anyway)
- (when (logbitp 31 (sb!alien:slot scp '%mips::sc-cause))
- (incf pc-offset sb!vm:n-word-bytes))
- (unless (<= 0 pc-offset
- (* (code-header-ref code sb!vm:code-code-size-slot)
- sb!vm:n-word-bytes))
- ;; We were in an assembly routine. Therefore, use the
- ;; LRA as the pc.
- (setf pc-offset
- (- (sb!vm:context-register scp sb!vm::lra-offset)
- (get-lisp-obj-address code)
- code-header-len)))
- (return
- (if (eq (%code-debug-info code) :bogus-lra)
- (let ((real-lra (code-header-ref code
- real-lra-slot)))
- (values (lra-code-header real-lra)
- (get-header-data real-lra)
- nil))
- (values code pc-offset scp)))))))))))
+ (let ((scp (nth-interrupt-context index)))
+ (when (= (sap-int frame-pointer)
+ (sb!vm:context-register scp sb!vm::cfp-offset))
+ (without-gcing
+ (let ((code (code-object-from-bits
+ (sb!vm:context-register scp sb!vm::code-offset))))
+ (when (symbolp code)
+ (return (values code 0 scp)))
+ (let* ((code-header-len (* (get-header-data code)
+ sb!vm:n-word-bytes))
+ (pc-offset
+ (- (sap-int (sb!vm:context-pc scp))
+ (- (get-lisp-obj-address code)
+ sb!vm:other-pointer-lowtag)
+ code-header-len)))
+ ;; Check to see whether we were executing in a branch
+ ;; delay slot.
+ #!+(or pmax sgi) ; pmax only (and broken anyway)
+ (when (logbitp 31 (sb!alien:slot scp '%mips::sc-cause))
+ (incf pc-offset sb!vm:n-word-bytes))
+ (let ((code-size (* (code-header-ref code
+ sb!vm:code-code-size-slot)
+ sb!vm:n-word-bytes)))
+ (unless (<= 0 pc-offset code-size)
+ ;; We were in an assembly routine.
+ (multiple-value-bind (new-pc-offset computed-return)
+ (find-pc-from-assembly-fun code scp)
+ (setf pc-offset new-pc-offset)
+ (unless (<= 0 pc-offset code-size)
+ (cerror
+ "Set PC-OFFSET to zero and continue backtrace."
+ 'bug
+ :format-control
+ "~@<PC-OFFSET (~D) not in code object. Frame details:~
+ ~2I~:@_PC: #X~X~:@_CODE: ~S~:@_CODE FUN: ~S~:@_LRA: ~
+ #X~X~:@_COMPUTED RETURN: #X~X.~:>"
+ :format-arguments
+ (list pc-offset
+ (sap-int (sb!vm:context-pc scp))
+ code
+ (%code-entry-points code)
+ (sb!vm:context-register scp sb!vm::lra-offset)
+ computed-return))
+ ;; We failed to pinpoint where PC is, but set
+ ;; pc-offset to 0 to keep the backtrace from
+ ;; exploding.
+ (setf pc-offset 0)))))
+ (return
+ (if (eq (%code-debug-info code) :bogus-lra)
+ (let ((real-lra (code-header-ref code
+ real-lra-slot)))
+ (values (lra-code-header real-lra)
+ (get-header-data real-lra)
+ nil))
+ (values code pc-offset scp))))))))))
+
+#!-x86
+(defun find-pc-from-assembly-fun (code scp)
+ "Finds the PC for the return from an assembly routine properly.
+For some architectures (such as PPC) this will not be the $LRA
+register."
+ (let ((return-machine-address (sb!vm::return-machine-address scp))
+ (code-header-len (* (get-header-data code) sb!vm:n-word-bytes)))
+ (values (- return-machine-address
+ (- (get-lisp-obj-address code)
+ sb!vm:other-pointer-lowtag)
+ code-header-len)
+ return-machine-address)))