From e48026257ea92807b2a5ee799476be198fc64dd6 Mon Sep 17 00:00:00 2001 From: William Harold Newman Date: Fri, 10 Aug 2001 18:50:46 +0000 Subject: [PATCH] 0.pre7.9: merged Dan Barlow patch from sbcl-devel 2001-08-10 (fix for TRACE on Alpha, fix for os_flush_icache() on Alpha, fix for environ in shared libs, and misc. tidying) --- src/code/debug-int.lisp | 6 +- src/code/run-program.lisp | 15 +++++ src/cold/shared.lisp | 2 +- src/compiler/alpha/insts.lisp | 2 +- src/runtime/alpha-arch.c | 136 ++++++++++++++++++++++------------------- src/runtime/alpha-assem.S | 4 +- src/runtime/alpha-linux-os.c | 15 ++--- src/runtime/breakpoint.c | 15 ++++- src/runtime/interrupt.c | 1 + version.lisp-expr | 2 +- 10 files changed, 115 insertions(+), 83 deletions(-) diff --git a/src/code/debug-int.lisp b/src/code/debug-int.lisp index 83378bd..d01cafd 100644 --- a/src/code/debug-int.lisp +++ b/src/code/debug-int.lisp @@ -3748,8 +3748,10 @@ ;; so we just leave it up to the C code. (breakpoint-do-displaced-inst signal-context (breakpoint-data-instruction data)) - ; Under HPUX we can't sigreturn so bp-do-disp-i has to return. - #!-(or hpux irix x86) + ;; Some platforms have no usable sigreturn() call. If your + ;; implementation of arch_do_displaced_inst() doesn't sigreturn(), + ;; add it to this list. + #!-(or hpux irix x86 alpha) (error "BREAKPOINT-DO-DISPLACED-INST returned?")))) (defun invoke-breakpoint-hooks (breakpoints component offset) diff --git a/src/code/run-program.lisp b/src/code/run-program.lisp index b7fb7c8..1dad7f9 100644 --- a/src/code/run-program.lisp +++ b/src/code/run-program.lisp @@ -46,6 +46,21 @@ ;;;; visible at GENESIS time. (def-alien-variable "environ" (* c-string)) +(push (lambda () + ;; We redo this here to protect ourselves from this scenario: + ;; * Build under one version of shared lib, save a core. + ;; * Load core under another version of shared lib. ("Now + ;; where was environ again?" SIGSEGV, etc.) + ;; Obviously it's a KLUDGE to do this hack for every alien + ;; variable, but as it happens, as of sbcl-0.7.0 this is the + ;; only alien variable used to implement SBCL, so it's not + ;; worth coming up with a general solution. (A general + ;; solution would be nice for users who want to have their + ;; alien code be preserved across a save/load cycle, but this + ;; problem with alien variables is only one of several + ;; problems which'd need to be solved before that can happen.) + (def-alien-variable "environ" (* c-string))) + *after-save-initializations*) (defun posix-environ () "Return the Unix environment (\"man environ\") as a list of SIMPLE-STRINGs." diff --git a/src/cold/shared.lisp b/src/cold/shared.lisp index d088aa2..8fe5a54 100644 --- a/src/cold/shared.lisp +++ b/src/cold/shared.lisp @@ -32,7 +32,7 @@ #+(and sbcl alpha) ; SBCL/Alpha uses stop-and-copy, and Alphas have lotso RAM. (progn (sb-ext:gc-off) - (setf (bytes-consed-between-gcs) (* 20 (expt 10 6))) + (setf (sb-ext:bytes-consed-between-gcs) (* 20 (expt 10 6))) (sb-ext:gc-on) (sb-ext:gc)) diff --git a/src/compiler/alpha/insts.lisp b/src/compiler/alpha/insts.lisp index 1442cb7..147b872 100644 --- a/src/compiler/alpha/insts.lisp +++ b/src/compiler/alpha/insts.lisp @@ -440,7 +440,7 @@ (define-instruction gentrap (segment code) (:printer call-pal ((palcode #xaa0000))) (:emitter - (emit-lword segment #x000080) + (emit-lword segment #x000081) ;actually bugchk (emit-lword segment code))) (define-instruction-macro move (src dst) diff --git a/src/runtime/alpha-arch.c b/src/runtime/alpha-arch.c index 001bc18..066355f 100644 --- a/src/runtime/alpha-arch.c +++ b/src/runtime/alpha-arch.c @@ -136,7 +136,6 @@ unsigned long arch_install_breakpoint(void *pc) unsigned int *ptr = (unsigned int *)pc; unsigned long result = (unsigned long) *ptr; *ptr = BREAKPOINT_INST; - *(ptr+1)=trap_Breakpoint; os_flush_icache((os_vm_address_t)ptr, sizeof(unsigned long)); @@ -164,7 +163,6 @@ emulate_branch(os_context_t *context,unsigned long orig_inst) int op = orig_inst >> 26; int reg_a = (orig_inst >> 21) & 0x1f; int reg_b = (orig_inst >> 16) & 0x1f; - int fn = orig_inst & 0xffff; int disp = (orig_inst&(1<<20)) ? orig_inst | (-1 << 21) : orig_inst&0x1fffff; int next_pc = *os_context_pc_addr(context); int branch = 0; /* was NULL; */ @@ -231,70 +229,101 @@ emulate_branch(os_context_t *context,unsigned long orig_inst) static sigset_t orig_sigmask; +/* Perform the instruction that we overwrote with a breakpoint. As we + * don't have a single-step facility, this means we have to: + * - put the instruction back + * - put a second breakpoint at the following instruction, + * set after_breakpoint and continue execution. + * + * When the second breakpoint is hit (very shortly thereafter, we hope) + * sigtrap_handler gets called again, but follows the AfterBreakpoint + * arm, which + * - puts a bpt back in the first breakpoint place (running across a + * breakpoint shouldn't cause it to be uninstalled) + * - replaces the second bpt with the instruction it was meant to be + * - carries on + * + * Clear? + */ + void arch_do_displaced_inst(os_context_t *context,unsigned int orig_inst) { + /* Apparent off-by-one errors ahoy. If you consult the Alpha ARM, + * it will tell you that after a BPT, the saved PC is the address + * of the instruction _after_ the instruction that caused the trap. + * + * However, we decremented PC by 4 before calling the Lisp-level + * handler that calls this routine (see alpha-arch.c line 322 and + * friends) so when we get to this point PC is actually pointing + * at the BPT instruction itself. This is good, because this is + * where we want to restart execution when we do that */ + unsigned int *pc=(unsigned int *)(*os_context_pc_addr(context)); unsigned int *next_pc; - unsigned int next_inst; int op = orig_inst >> 26;; - fprintf(stderr,"arch_do_displaced_inst depends on sigreturn, which is not implemented and will\nalways fail\n"); + orig_sigmask = *os_context_sigmask_addr(context); sigaddset_blockable(os_context_sigmask_addr(context)); - /* Figure out where the displaced inst is going. */ - if(op == 0x1a || (op&0xf) == 0x30) /* branch...ugh */ - /* The cast to long is just to shut gcc up. */ - next_pc = (unsigned int *)((long)emulate_branch(context,orig_inst)); - else - next_pc = pc+1; - /* Put the original instruction back. */ *pc = orig_inst; os_flush_icache((os_vm_address_t)pc, sizeof(unsigned long)); skipped_break_addr = pc; + /* Figure out where we will end up after running the displaced + * instruction */ + if(op == 0x1a || (op&0xf) == 0x30) /* a branch */ + /* The cast to long is just to shut gcc up. */ + next_pc = (unsigned int *)((long)emulate_branch(context,orig_inst)); + else + next_pc = pc+1; + /* Set the after breakpoint. */ displaced_after_inst = *next_pc; *next_pc = BREAKPOINT_INST; after_breakpoint=1; os_flush_icache((os_vm_address_t)next_pc, sizeof(unsigned long)); - - monitor_or_something(); - sigreturn(context); -} - -#define AfterBreakpoint 100 - -static void -sigill_handler(int signal, siginfo_t *siginfo, os_context_t *context) { - fake_foreign_function_call(context); - monitor_or_something(); } static void sigtrap_handler(int signal, siginfo_t *siginfo, os_context_t *context) { + unsigned int code; + /* Don't disallow recursive breakpoint traps. Otherwise, we can't */ /* use debugger breakpoints anywhere in here. */ - sigset_t *mask=(os_context_sigmask_addr(context)); - unsigned int code; - fprintf(stderr,"sigtrap_handler:signal %d context=%p ",signal,context); sigsetmask(mask); - /* this is different from how CMUCL does it. CMUCL used - * "call_pal PAL_gentrap", which doesn't do anything on Linux - * so screwed up our offsets in odd ways. We use "bpt" instead - */ - - /* probably we should - assert(*(unsigned int*)(*os_context_pc_addr(context)-4) == BREAKPOINT_INST) - but I've not decided a good way to handle it if it turns out not to be - */ + /* this is different from how CMUCL does it. CMUCL used "call_pal + * PAL_gentrap", which doesn't do anything on Linux (unless NL0 + * contains certain specific values). We use "bugchk" instead. + * It's (for our purposes) just the same as bpt but has a + * different opcode so we can test whether we're dealing with a + * breakpoint or a "system service" */ + + if((*(unsigned int*)(*os_context_pc_addr(context)-4))== BREAKPOINT_INST) { + if(after_breakpoint) { + /* see comments above arch_do_displaced_inst. This is where + * we reinsert the breakpoint that we removed earlier */ + + *os_context_pc_addr(context) -=4; + *skipped_break_addr = BREAKPOINT_INST; + os_flush_icache((os_vm_address_t)skipped_break_addr, + sizeof(unsigned long)); + skipped_break_addr = NULL; + *(unsigned int *)*os_context_pc_addr(context) = + displaced_after_inst; + os_flush_icache((os_vm_address_t)*os_context_pc_addr(context), sizeof(unsigned long)); + *os_context_sigmask_addr(context)= orig_sigmask; + after_breakpoint=0; /* false */ + return; + } else + code = trap_Breakpoint; + } else + /* a "system service" */ code=*((u32 *)(*os_context_pc_addr(context))); - fprintf(stderr,"pc=%lx code=%d, inst=%x\n", - *os_context_pc_addr(context), code, - *(unsigned int*)(*os_context_pc_addr(context)-4)); + switch (code) { case trap_PendingInterrupt: arch_skip_instruction(context); @@ -310,43 +339,33 @@ sigtrap_handler(int signal, siginfo_t *siginfo, os_context_t *context) interrupt_internal_error(signal, siginfo, context, code==trap_Cerror); break; - case trap_Breakpoint: + case trap_Breakpoint: /* call lisp-level handler */ *os_context_pc_addr(context) -=4; handle_breakpoint(signal, siginfo, context); break; case trap_FunctionEndBreakpoint: *os_context_pc_addr(context) -=4; - *os_context_pc_addr(context) = (int)handle_function_end_breakpoint(signal, siginfo, context); - break; - - case AfterBreakpoint: - *os_context_pc_addr(context) -=4; - *skipped_break_addr = BREAKPOINT_INST; - os_flush_icache((os_vm_address_t)skipped_break_addr, - sizeof(unsigned long)); - skipped_break_addr = NULL; - *(unsigned int *)*os_context_pc_addr(context) = displaced_after_inst; - os_flush_icache((os_vm_address_t)*os_context_pc_addr(context), sizeof(unsigned long)); - *os_context_sigmask_addr(context)= orig_sigmask; - after_breakpoint=0; /* NULL; */ + *os_context_pc_addr(context) = + (int)handle_function_end_breakpoint(signal, siginfo, context); break; default: + fprintf(stderr, "unidetified breakpoint/trap %d\n",code); interrupt_handle_now(signal, siginfo, context); break; } } -#define FIXNUM_VALUE(lispobj) (((int)lispobj)>>2) - static void sigfpe_handler(int signal, int code, os_context_t *context) { + /* what should this contain? interesting question. If it really + * is empty, why don't we just ignore the signal? -dan 2001.08.10 + */ } void arch_install_interrupt_handlers() { - undoably_install_low_level_interrupt_handler(SIGILL, sigill_handler); undoably_install_low_level_interrupt_handler(SIGTRAP, sigtrap_handler); undoably_install_low_level_interrupt_handler(SIGFPE, sigfpe_handler); } @@ -393,12 +412,3 @@ lispobj funcall3(lispobj function, lispobj arg0, lispobj arg1, lispobj arg2) return call_into_lisp(function, args, 3); } - -/* This is apparently called by emulate_branch, but isn't defined. So */ -/* just do nothing and hope it works... */ -void cacheflush(void) -{ - /* hoping probably isn't _actually_ enough. we should call_pal imb, - according to the arch ref manual - */ -} diff --git a/src/runtime/alpha-assem.S b/src/runtime/alpha-assem.S index 56d0047..ba97b81 100644 --- a/src/runtime/alpha-assem.S +++ b/src/runtime/alpha-assem.S @@ -257,7 +257,7 @@ start_of_tramps: .ent undefined_tramp_offset undefined_tramp = /* ### undefined_tramp_offset-call_into_lisp_LRA*/ 0x140+call_into_lisp_LRA_page undefined_tramp_offset: - bpt + call_pal PAL_bugchk .long trap_Error .byte 4 /* what are these numbers? */ .byte 23 @@ -311,7 +311,7 @@ function_end_breakpoint_guts: .globl function_end_breakpoint_trap function_end_breakpoint_trap: - call_pal PAL_gentrap + call_pal PAL_bugchk .long trap_FunctionEndBreakpoint br zero, function_end_breakpoint_trap diff --git a/src/runtime/alpha-linux-os.c b/src/runtime/alpha-linux-os.c index 8ea7001..3cb67b3 100644 --- a/src/runtime/alpha-linux-os.c +++ b/src/runtime/alpha-linux-os.c @@ -1,7 +1,6 @@ /* - * This is the x86 Linux incarnation of arch-dependent OS-dependent - * routines. See also "linux-os.c". - */ + * This is the Compaq/Digital Alpha Linux incarnation of + * arch-dependent OS-dependent routines. See also "linux-os.c". */ /* * This software is part of the SBCL system. See the README file for @@ -32,7 +31,6 @@ #include #include -/* #include */ #include #include #include @@ -41,6 +39,7 @@ size_t os_vm_page_size; #if defined GENCGC /* unlikely ... */ +#error SBCL Alpha does not work with the GENCGC #include "gencgc.h" #endif @@ -76,11 +75,5 @@ os_context_sigmask_addr(os_context_t *context) void os_flush_icache(os_vm_address_t address, os_vm_size_t length) { - /* XXX this really shouldn't be empty - - dan_b: asm volatile ("call_pal imb") - or just "imb" - also : : "memory" - - */ + asm volatile ("imb" : : : "memory" ); } diff --git a/src/runtime/breakpoint.c b/src/runtime/breakpoint.c index 9e95a8a..48f8aed 100644 --- a/src/runtime/breakpoint.c +++ b/src/runtime/breakpoint.c @@ -54,7 +54,15 @@ void breakpoint_remove(lispobj code_obj, int pc_offset, void breakpoint_do_displaced_inst(os_context_t* context, unsigned long orig_inst) { -#if !defined(hpux) && !defined(irix) && !defined(__i386__) + /* on platforms with sigreturn(), we go directly back from + * arch_do_displaced_inst() to lisp code, so we need to clean up + * our bindings now. (side note: I'd love to know in exactly what + * scenario the speed of breakpoint handling is critical enough to + * justify this maintenance mess) + * + * -dan 2001.08.09 */ + +#if !(defined(hpux) || defined(irix) || defined(__i386__) || defined(alpha)) undo_fake_foreign_function_call(context); #endif arch_do_displaced_inst(context, orig_inst); @@ -122,7 +130,10 @@ static int compute_offset(os_context_t *context, lispobj code) } } } - +/* FIXME: I can see no really good reason these couldn't be merged, but haven't + * tried. The sigprocmask() call would work just as well on alpha as it + * presumably does on x86 -dan 2001.08.10 + */ #ifndef __i386__ void handle_breakpoint(int signal, siginfo_t *info, os_context_t *context) { diff --git a/src/runtime/interrupt.c b/src/runtime/interrupt.c index 4b42d13..c516822 100644 --- a/src/runtime/interrupt.c +++ b/src/runtime/interrupt.c @@ -214,6 +214,7 @@ undo_fake_foreign_function_call(os_context_t *context) * FREE_INTERRUPT_CONTEXT_INDEX? If so, we should say so. And * perhaps yes, unbind_to_here() really would be clearer and less * fragile.. */ + /* dan (2001.08.10) thinks the above supposition is probably correct */ unbind(); #ifdef reg_ALLOC diff --git a/version.lisp-expr b/version.lisp-expr index bfb8e16..c6a13a5 100644 --- a/version.lisp-expr +++ b/version.lisp-expr @@ -16,4 +16,4 @@ ;;; four numeric fields, is used for versions which aren't released ;;; but correspond only to CVS tags or snapshots. -"0.pre7.8" +"0.pre7.9" -- 1.7.10.4