#define align_4byte 4
#define align_8byte 8
#define align_16byte 16
+#define align_page 4096
#else
#define align_4byte 2
#define align_8byte 3
#define align_16byte 4
+#define align_page 12
#endif
/*
#define SIZE(name)
#endif
+/* Helper macros for access to thread-locals slots for both OS types:
+ * ------------------------------------------------------------------------
+ *
+ * Windows TEB block
+ * ================== __________
+ * | Win32 %FS base | ----> | | 0
+ * ================== | | 1
+ * z z
+ * TLS slots start here> |XXXXXXXX| e10 = TEB_STATIC_TLS_SLOTS_OFFSET
+ * |XXXXXXXX| e11
+ * z ... z
+ * |XXXXXXXX| e4e
+ * TLS ends here> ,- |XXXXXXXX| e4f = TEB_STATIC_TLS_SLOTS_OFFSET+63
+ * / z z
+ * | ---------- "os_address" ----.
+ * | |
+ * | big blob of SBCL-specific thread-local data |
+ * | |----------------------------------------| <--'
+ * | | CONTROL, BINDING, ALIEN STACK |
+ * | z z
+ * ================== | |----------------------------------------|
+ * | Linux %FS base | -->| | FFI stack pointer |
+ * ================== | | (extra page for mprotect) |
+ * \ |----------------------------------------|
+ * (union p_t_d) -----> \-> | struct thread { | dynamic_values[0] |
+ * . | ... | [1] |
+ * . z ... z ... z
+ * [tls data begins] | } | ... | <-
+ * [declared end of p_t_d] |----------------------------------------| . |
+ * . | ... | . |
+ * . | [TLS_SIZE-1] | <-|
+ * [tls data actually ends] |----------------------------------------| |
+ * . | ALTSTACK | |
+ * . |----------------------------------------| |
+ * . | struct nonpointer_thread_data { } | |
+ * . ------------------------------------------ |
+ * [blob actually ends] |
+ * /
+ * /
+ * /
+ * ______________________ /
+ * | struct symbol { | /
+ * z ... z /
+ * | fixnum tls_index; // fixnum value relative to union /
+ * | } | (< TLS_SIZE = 4096)
+ * ---------------------|
+ */
+#ifdef LISP_FEATURE_WIN32
+# define TEB_STATIC_TLS_SLOTS_OFFSET 0xE10
+# define TEB_SBCL_THREAD_BASE_OFFSET (TEB_STATIC_TLS_SLOTS_OFFSET+(63*4))
+# define SBCL_THREAD_BASE_EA %fs:TEB_SBCL_THREAD_BASE_OFFSET
+# define MAYBE_FS(addr) addr
+# define LoadTlSymbolValueAddress(symbol,reg) ; \
+ movl SBCL_THREAD_BASE_EA, reg ; \
+ addl (symbol+SYMBOL_TLS_INDEX_OFFSET), reg ;
+# define LoadCurrentThreadSlot(offset,reg); \
+ movl SBCL_THREAD_BASE_EA, reg ; \
+ movl offset(reg), reg ;
+#elif defined(LISP_FEATURE_LINUX) || defined(LISP_FEATURE_SUNOS) || defined(LISP_FEATURE_FREEBSD)
+ /* see comment in arch_os_thread_init */
+# define SBCL_THREAD_BASE_EA %fs:THREAD_SELFPTR_OFFSET
+# define MAYBE_FS(addr) addr
+#else
+ /* perhaps there's an OS out there that actually supports %fs without
+ * jumping through hoops, so just in case, here a default definition: */
+# define SBCL_THREAD_BASE_EA $0
+# define MAYBE_FS(addr) %fs:addr
+#endif
+
+/* gas can't parse 4096LU; redefine */
+#if BACKEND_PAGE_BYTES == 4096
+# undef BACKEND_PAGE_BYTES
+# define BACKEND_PAGE_BYTES 4096
+#elif BACKEND_PAGE_BYTES == 32768
+# undef BACKEND_PAGE_BYTES
+# define BACKEND_PAGE_BYTES 32768
+#else
+# error BACKEND_PAGE_BYTES mismatch
+#endif
+
+/* OAOOM because we don't have the C headers here */
+#define THREAD_CSP_PAGE_SIZE BACKEND_PAGE_BYTES
+
+/* the CSP page sits right before the thread */
+#define THREAD_SAVED_CSP_OFFSET (-THREAD_CSP_PAGE_SIZE)
+
/*
* x86/darwin (as of MacOS X 10.4.5) doesn't reliably file signal
* handlers (SIGTRAP or Mach exception handlers) for 0xCC, wo we have
* FIXME & OAOOM: This duplicates call-out in src/compiler/x86/c-call.lisp,
* so if you tweak this, change that too!
*/
+/*
+ * Note on sections specific to LISP_FEATURE_SB_SAFEPOINT:
+ *
+ * The code below is essential to safepoint-based garbage collection,
+ * and several details need to be considered for correct implementation.
+ *
+ * The stack spilling approach:
+ * On SB-SAFEPOINT platforms, the CALL-OUT vop is defined to spill all
+ * live Lisp TNs to the stack to provide information for conservative
+ * GC cooperatively (avoiding the need to retrieve register values
+ * from POSIX signal contexts or Windows GetThreadContext()).
+ *
+ * Finding the SP at all:
+ * The main remaining value needed by GC is the stack pointer (SP) at
+ * the moment of entering the foreign function. For this purpose, a
+ * thread-local field for the SP is used. Two stores to that field
+ * are done for each C call, one to save the SP before calling out and
+ * and one to undo that store afterwards.
+ *
+ * Stores as synchronization points:
+ * These two stores delimit the C call: While the SP is set, our
+ * thread is known not to run Lisp code: During GC, memory protection
+ * ensures that no thread proceeds across stores.
+ *
+ * The return PC issue:
+ * (Note that CALL-OUT has, in principle, two versions: Inline
+ * assembly in the VOP -or- alternatively the out-of-line version you
+ * are currently reading. In reality, safepoint builds currently
+ * lack the inline code entirely.)
+ *
+ * Both versions need to take special care with the return PC:
+ * - In the inline version of the code (if it existed), the two stores
+ * would be done directly in the CALL-OUT vop. In that theoretical
+ * implementation, there is a time interval between return of the
+ * actual C call and a second SP store during which the return
+ * address might not be on the stack anymore.
+ * - In this out-of-line version, the stores are done during
+ * call_into_c's frame, but an equivalent problem arises: In order
+ * to present the stack of arguments as our foreign function expects
+ * them, call_into_c has to pop the Lisp return address into a
+ * register first; this register has to be preserved by GENCGC
+ * separately: our return address is not in the stack anymore.
+ * In both case, stack scanning alone is not sufficient to pin
+ * the return address, and we communicate it to GC explicitly
+ * in addition to the SP.
+ *
+ * Note on look-alike accessor macros with vastly different behaviour:
+ * THREAD_PC_AROUND_FOREIGN_CALL_OFFSET is an "ordinary" field of the
+ * struct thread, whereas THREAD_SAVED_CSP_OFFSET is a synchronization
+ * point on a potentially write-protected page.
+*/
+
.text
.align align_16byte,0x90
.globl GNAME(call_into_c)
popl %ebx
/* Setup the NPX for C */
+ /* The VOP says regarding CLD: "Clear out DF: Darwin, Windows,
+ * and Solaris at least require this, and it should not hurt
+ * others either." call_into_c didn't have it, but better safe than
+ * sorry. */
+ cld
fstp %st(0)
fstp %st(0)
fstp %st(0)
fstp %st(0)
fstp %st(0)
+#ifdef LISP_FEATURE_SB_SAFEPOINT
+ /* enter safe region: store SP and return PC */
+ movl SBCL_THREAD_BASE_EA,%edi
+ movl %esp,MAYBE_FS(THREAD_SAVED_CSP_OFFSET(%edi))
+ movl %ebx,MAYBE_FS(THREAD_PC_AROUND_FOREIGN_CALL_OFFSET(%edi))
+#endif
+
+ /* foreign call, preserving ESI, EDI, and EBX */
call *%eax # normal callout using Lisp stack
- movl %eax,%ecx # remember integer return value
+ /* return values now in eax/edx OR st(0) */
+
+#ifdef LISP_FEATURE_SB_SAFEPOINT
+ /* leave region: clear the SP! (Also unpin the return PC.) */
+ xorl %ecx,%ecx
+ movl %ecx,MAYBE_FS(THREAD_SAVED_CSP_OFFSET(%edi))
+ movl %ecx,MAYBE_FS(THREAD_PC_AROUND_FOREIGN_CALL_OFFSET(%edi))
+#endif
+
+ movl %eax,%ecx # remember integer return value
/* Check for a return FP value. */
fxam
/* We don't need to restore eax, because the result is in st(0). */
-/* Return. FIXME: It would be nice to restructure this to use RET. */
+/* Return. FIXME: It would be nice to restructure this to use RET. */
jmp *%ebx
SIZE(GNAME(call_into_c))
GNAME(call_into_lisp):
pushl %ebp # Save old frame pointer.
movl %esp,%ebp # Establish new frame.
+
Lstack:
/* Save the NPX state */
fwait # Catch any pending NPX exceptions.
#ifdef LISP_FEATURE_WIN32
/* Establish an SEH frame. */
#ifdef LISP_FEATURE_SB_THREAD
- /* FIXME: need to save BSP here. */
-#error "need to save BSP here, but don't know how yet."
+ /* Save binding stack pointer */
+ subl $4, %esp
+ pushl %eax
+ movl SBCL_THREAD_BASE_EA, %eax
+ movl THREAD_BINDING_STACK_POINTER_OFFSET(%eax), %eax
+ movl %eax, 4(%esp)
+ popl %eax
#else
pushl BINDING_STACK_POINTER + SYMBOL_VALUE_OFFSET
#endif
#ifdef LISP_FEATURE_WIN32
/* Remove our SEH frame. */
+ mov %fs:0,%esp
popl %fs:0
add $8, %esp
#endif
#define START_REGION GNAME(boxed_region)
#endif
-#define ALLOC_OVERFLOW(size) \
- /* Calculate the size for the allocation. */ \
- subl START_REGION,size; \
- ALLOC(size)
+#if defined(LISP_FEATURE_SB_THREAD) && defined(LISP_FEATURE_WIN32)
+#define ALLOC_OVERFLOW(size,scratch) \
+ movl SBCL_THREAD_BASE_EA, scratch; \
+ /* Calculate the size for the allocation. */ \
+ subl THREAD_ALLOC_REGION_OFFSET(scratch),size; \
+ ALLOC(size)
+#else
+#define ALLOC_OVERFLOW(size,scratch) \
+ /* Calculate the size for the allocation. */ \
+ subl START_REGION,size; \
+ ALLOC(size)
+#endif
/* This routine handles an overflow with eax=crfp+size. So the
size=eax-crfp. */
GNAME(alloc_overflow_eax):
pushl %ecx # Save ecx
pushl %edx # Save edx
- ALLOC_OVERFLOW(%eax)
+ ALLOC_OVERFLOW(%eax,%edx)
popl %edx # Restore edx.
popl %ecx # Restore ecx.
ret
GNAME(alloc_overflow_ecx):
pushl %eax # Save eax
pushl %edx # Save edx
- ALLOC_OVERFLOW(%ecx)
+ ALLOC_OVERFLOW(%ecx,%edx)
movl %eax,%ecx # setup the destination.
popl %edx # Restore edx.
popl %eax # Restore eax.
GNAME(alloc_overflow_edx):
pushl %eax # Save eax
pushl %ecx # Save ecx
- ALLOC_OVERFLOW(%edx)
+ ALLOC_OVERFLOW(%edx,%ecx)
movl %eax,%edx # setup the destination.
popl %ecx # Restore ecx.
popl %eax # Restore eax.
pushl %eax # Save eax
pushl %ecx # Save ecx
pushl %edx # Save edx
- ALLOC_OVERFLOW(%ebx)
+ ALLOC_OVERFLOW(%ebx,%edx)
movl %eax,%ebx # setup the destination.
popl %edx # Restore edx.
popl %ecx # Restore ecx.
pushl %eax # Save eax
pushl %ecx # Save ecx
pushl %edx # Save edx
- ALLOC_OVERFLOW(%esi)
+ ALLOC_OVERFLOW(%esi,%edx)
movl %eax,%esi # setup the destination.
popl %edx # Restore edx.
popl %ecx # Restore ecx.
pushl %eax # Save eax
pushl %ecx # Save ecx
pushl %edx # Save edx
- ALLOC_OVERFLOW(%edi)
+ ALLOC_OVERFLOW(%edi,%edx)
movl %eax,%edi # setup the destination.
popl %edx # Restore edx.
popl %ecx # Restore ecx.