X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Falpha-arch.c;h=5abdf241102451fd5bb2c3b07355c2710430d330;hb=90ca09b75fbc3b63b2f7d09c67b04b866dd783f6;hp=b0f9fad21c5d17b66c4cce8c0d8ff7b7d71ae282;hpb=dfa55a883f94470267b626dae77ce7e7dfac3df6;p=sbcl.git diff --git a/src/runtime/alpha-arch.c b/src/runtime/alpha-arch.c index b0f9fad..5abdf24 100644 --- a/src/runtime/alpha-arch.c +++ b/src/runtime/alpha-arch.c @@ -9,12 +9,10 @@ * files for more information. */ -/* note that although superficially it appears that we use +/* Note that although superficially it appears that we use * os_context_t like we ought to, we actually just assume its a * ucontext in places. Naughty */ - - #include #include #include /* for PAL_gentrap */ @@ -31,14 +29,17 @@ #include "interrupt.h" #include "interr.h" #include "breakpoint.h" +#include "monitor.h" extern char call_into_lisp_LRA[], call_into_lisp_end[]; extern size_t os_vm_page_size; #define BREAKPOINT_INST 0x80 -void arch_init(void) +void +arch_init(void) { - /* this must be called _after_ os_init, so we know what the page size is */ + /* This must be called _after_ os_init, so we know what the page + * size is. */ if(mmap((os_vm_address_t) call_into_lisp_LRA_page,os_vm_page_size, OS_VM_PROT_ALL,MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED,-1,0) == (os_vm_address_t) -1) @@ -46,8 +47,8 @@ void arch_init(void) /* call_into_lisp_LRA is a collection of trampolines written in asm - * see alpha-assem.S. We copy it to call_into_lisp_LRA_page where - * VOPs and things can find it (I don't know why they can't find it - * where it was to start with). */ + * VOPs and things can find it. (I don't know why they can't find it + * where it was to start with.) */ bcopy(call_into_lisp_LRA,(void *)call_into_lisp_LRA_page,os_vm_page_size); os_flush_icache((os_vm_address_t)call_into_lisp_LRA_page, @@ -58,49 +59,53 @@ void arch_init(void) os_vm_address_t arch_get_bad_addr (int sig, siginfo_t *code, os_context_t *context) { - unsigned int badinst; + unsigned int badinst; - /* instructions are 32 bit quantities */ - unsigned int *pc ; - /* fprintf(stderr,"arch_get_bad_addr %d %p %p\n", - sig, code, context); */ - pc= (unsigned int *)(*os_context_pc_addr(context)); + /* Instructions are 32 bit quantities. */ + unsigned int *pc ; + /* fprintf(stderr,"arch_get_bad_addr %d %p %p\n", + sig, code, context); */ + pc= (unsigned int *)(*os_context_pc_addr(context)); - if(((unsigned long)pc) & 3) - return NULL; /* in what case would pc be unaligned? */ + if(((unsigned long)pc) & 3) { + return NULL; /* In what case would pc be unaligned?? */ + } - if( (pc < READ_ONLY_SPACE_START || - pc >= READ_ONLY_SPACE_START+READ_ONLY_SPACE_SIZE) && - (pc < current_dynamic_space || - pc >= current_dynamic_space + DYNAMIC_SPACE_SIZE)) - return NULL; + if( (pc < READ_ONLY_SPACE_START || + pc >= READ_ONLY_SPACE_START+READ_ONLY_SPACE_SIZE) && + (pc < current_dynamic_space || + pc >= current_dynamic_space + DYNAMIC_SPACE_SIZE)) + return NULL; - badinst = *pc; + badinst = *pc; - if(((badinst>>27)!=0x16) /* STL or STQ */ - && ((badinst>>27)!=0x13)) /* STS or STT */ - return NULL; /* Otherwise forget about address */ + if(((badinst>>27)!=0x16) /* STL or STQ */ + && ((badinst>>27)!=0x13)) /* STS or STT */ + return NULL; /* Otherwise forget about address. */ - return (os_vm_address_t) - (*os_context_register_addr(context,((badinst>>16)&0x1f)) - +(badinst&0xffff)); + return (os_vm_address_t) + (*os_context_register_addr(context,((badinst>>16)&0x1f)) + +(badinst&0xffff)); } -void arch_skip_instruction(os_context_t *context) +void +arch_skip_instruction(os_context_t *context) { - /* this may be complete rubbish, as (at least for traps) pc points - * _after_ the instruction that caused us to be here anyway + /* This may be complete rubbish, as (at least for traps) pc points + * _after_ the instruction that caused us to be here anyway. */ ((char*)*os_context_pc_addr(context)) +=4; } -unsigned char *arch_internal_error_arguments(os_context_t *context) +unsigned char * +arch_internal_error_arguments(os_context_t *context) { - return (unsigned char *)(*os_context_pc_addr(context)+4); + return (unsigned char *)(*os_context_pc_addr(context)+4); } -boolean arch_pseudo_atomic_atomic(os_context_t *context) +boolean +arch_pseudo_atomic_atomic(os_context_t *context) { - return ((*os_context_register_addr(context,reg_ALLOC)) & 1); + return ((*os_context_register_addr(context,reg_ALLOC)) & 1); } void arch_set_pseudo_atomic_interrupted(os_context_t *context) @@ -118,10 +123,10 @@ void arch_set_pseudo_atomic_interrupted(os_context_t *context) /* [1] This behaviour can be changed with osf_setsysinfo, but cmucl * didn't use that */ -#ifdef linux - *os_context_register_addr(context,reg_ALLOC) |= (1L<<63); +#ifdef __linux__ + *os_context_register_addr(context,reg_ALLOC) |= (1L<<63); #else - *os_context_register_addr(context,reg_ALLOC) |= 2; + *os_context_register_addr(context,reg_ALLOC) |= 2; #endif } @@ -131,7 +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)); @@ -140,155 +144,192 @@ unsigned long arch_install_breakpoint(void *pc) void arch_remove_breakpoint(void *pc, unsigned long orig_inst) { - /* was (unsigned int) but gcc complains. Changed to mirror - install_breakpoint above */ - unsigned long *ptr=(unsigned long *)pc; - *ptr = orig_inst; - os_flush_icache((os_vm_address_t)pc, sizeof(unsigned long)); + /* was (unsigned int) but gcc complains. Changed to mirror + * install_breakpoint() above */ + unsigned long *ptr=(unsigned long *)pc; + *ptr = orig_inst; + os_flush_icache((os_vm_address_t)pc, sizeof(unsigned long)); } static unsigned int *skipped_break_addr, displaced_after_inst, after_breakpoint; -/* Returns a PC value. Lisp code is all in the 32-bit-addressable - space,so we should be ok with an unsigned int */ - +/* This returns a PC value. Lisp code is all in the 32-bit-addressable + * space, so we should be ok with an unsigned int. */ unsigned int 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; */ - - switch(op) { - case 0x1a: /* jmp, jsr, jsr_coroutine, ret */ - *os_context_register_addr(context,reg_a)=*os_context_pc_addr(context); - *os_context_pc_addr(context)=*os_context_register_addr(context,reg_b)& ~3; - break; - case 0x30: /* br */ - *os_context_register_addr(context,reg_a)=*os_context_pc_addr(context); - branch = 1; - break; - case 0x31: /* fbeq */ - if(*(os_context_fpregister_addr(context,reg_a))==0) branch = 1; - break; - case 0x32: /* fblt */ - if(*os_context_fpregister_addr(context,reg_a)<0) branch = 1; - break; - case 0x33: /* fble */ - if(*os_context_fpregister_addr(context,reg_a)<=0) branch = 1; - break; - case 0x34: /* bsr */ - *os_context_register_addr(context,reg_a)=*os_context_pc_addr(context); - branch = 1; - break; - case 0x35: /* fbne */ - if(*os_context_register_addr(context,reg_a)!=0) branch = 1; - break; - case 0x36: /* fbge */ - if(*os_context_fpregister_addr(context,reg_a)>=0) branch = 1; - break; - case 0x37: /* fbgt */ - if(*os_context_fpregister_addr(context,reg_a)>0) branch = 1; - break; - case 0x38: /* blbc */ - if((*os_context_register_addr(context,reg_a)&1) == 0) branch = 1; - break; - case 0x39: /* beq */ - if(*os_context_register_addr(context,reg_a)==0) branch = 1; - break; - case 0x3a: /* blt */ - if(*os_context_register_addr(context,reg_a)<0) branch = 1; - break; - case 0x3b: /* ble */ - if(*os_context_register_addr(context,reg_a)<=0) branch = 1; - break; - case 0x3c: /* blbs */ - if((*os_context_register_addr(context,reg_a)&1)!=0) branch = 1; - break; - case 0x3d: /* bne */ - if(*os_context_register_addr(context,reg_a)!=0) branch = 1; - break; - case 0x3e: /* bge */ - if(*os_context_register_addr(context,reg_a)>=0) branch = 1; - break; - case 0x3f: /* bgt */ - if(*os_context_register_addr(context,reg_a)>0) branch = 1; - break; - } - if(branch) next_pc += disp*4; - return next_pc; + int op = orig_inst >> 26; + int reg_a = (orig_inst >> 21) & 0x1f; + int reg_b = (orig_inst >> 16) & 0x1f; + 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; */ + + switch(op) { + case 0x1a: /* jmp, jsr, jsr_coroutine, ret */ + *os_context_register_addr(context,reg_a) = + *os_context_pc_addr(context); + *os_context_pc_addr(context) = + *os_context_register_addr(context,reg_b)& ~3; + break; + case 0x30: /* br */ + *os_context_register_addr(context,reg_a)=*os_context_pc_addr(context); + branch = 1; + break; + case 0x31: /* fbeq */ + if(*(os_context_fpregister_addr(context,reg_a))==0) branch = 1; + break; + case 0x32: /* fblt */ + if(*os_context_fpregister_addr(context,reg_a)<0) branch = 1; + break; + case 0x33: /* fble */ + if(*os_context_fpregister_addr(context,reg_a)<=0) branch = 1; + break; + case 0x34: /* bsr */ + *os_context_register_addr(context,reg_a)=*os_context_pc_addr(context); + branch = 1; + break; + case 0x35: /* fbne */ + if(*os_context_register_addr(context,reg_a)!=0) branch = 1; + break; + case 0x36: /* fbge */ + if(*os_context_fpregister_addr(context,reg_a)>=0) branch = 1; + break; + case 0x37: /* fbgt */ + if(*os_context_fpregister_addr(context,reg_a)>0) branch = 1; + break; + case 0x38: /* blbc */ + if((*os_context_register_addr(context,reg_a)&1) == 0) branch = 1; + break; + case 0x39: /* beq */ + if(*os_context_register_addr(context,reg_a)==0) branch = 1; + break; + case 0x3a: /* blt */ + if(*os_context_register_addr(context,reg_a)<0) branch = 1; + break; + case 0x3b: /* ble */ + if(*os_context_register_addr(context,reg_a)<=0) branch = 1; + break; + case 0x3c: /* blbs */ + if((*os_context_register_addr(context,reg_a)&1)!=0) branch = 1; + break; + case 0x3d: /* bne */ + if(*os_context_register_addr(context,reg_a)!=0) branch = 1; + break; + case 0x3e: /* bge */ + if(*os_context_register_addr(context,reg_a)>=0) branch = 1; + break; + case 0x3f: /* bgt */ + if(*os_context_register_addr(context,reg_a)>0) branch = 1; + break; + } + if (branch) + next_pc += disp*4; + return next_pc; } 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) { - 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; - - /* 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)); - - ldb_monitor("sigreturn is not implemented and just failed"); - sigreturn(context); -} - -#define AfterBreakpoint 100 - -static void sigill_handler(int signal, siginfo_t *siginfo, os_context_t *context) { - fake_foreign_function_call(context); - ldb_monitor(); + /* 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; + int op = orig_inst >> 26;; + + orig_sigmask = *os_context_sigmask_addr(context); + sigaddset_blockable(os_context_sigmask_addr(context)); + + /* 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)); } -static void sigtrap_handler(int signal, siginfo_t *siginfo, os_context_t *context) +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); @@ -304,45 +345,35 @@ static void sigtrap_handler(int signal, siginfo_t *siginfo, os_context_t *contex 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: + case trap_FunEndBreakpoint: *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_fun_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() { - interrupt_install_low_level_handler(SIGILL,sigill_handler); - interrupt_install_low_level_handler(SIGTRAP,sigtrap_handler); - interrupt_install_low_level_handler(SIGFPE,sigfpe_handler); + undoably_install_low_level_interrupt_handler(SIGTRAP, sigtrap_handler); + undoably_install_low_level_interrupt_handler(SIGFPE, sigfpe_handler); } extern lispobj call_into_lisp(lispobj fun, lispobj *args, int nargs); @@ -387,13 +418,3 @@ 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 - */ -}