* src/vm/jit/i386/linux/md-os.c: Simplified signal handlers.

* src/vm/jit/i386/md-trap.h (MD_TRAP_COMPILER_FIXUP): Implemented.
* src/vm/jit/i386/md.c (md_trap_decode): Implemented.
* src/vm/jit/trap.cpp (trap_handle) [__I386__]: Fixed minor conflict.

--HG--
branch : new-trap-decoding

diff --git a/src/vm/jit/i386/linux/md-os.c b/src/vm/jit/i386/linux/md-os.c
index 1f72d58d2ffca4f21a73fbd7508651312c9abb18..1417ec01a073347972182d543c5e6f1ac661c1bb 100644 (file)
--- a/src/vm/jit/i386/linux/md-os.c
+++ b/src/vm/jit/i386/linux/md-os.c
@@ -2,6 +2,7 @@
 
    Copyright (C) 1996-2005, 2006, 2007, 2008
    CACAOVM - Verein zur Foerderung der freien virtuellen Maschine CACAO
+   Copyright (C) 2009 Theobroma Systems Ltd.
 
    This file is part of CACAO.
 
@@ -37,196 +38,55 @@
 
 #include "threads/thread.hpp"
 
-#include "vm/jit/builtin.hpp"
 #include "vm/signallocal.hpp"
 
-#include "vm/jit/asmpart.h"
 #include "vm/jit/executionstate.h"
-#include "vm/jit/stacktrace.hpp"
 #include "vm/jit/trap.hpp"
 
 
-/* md_signal_handler_sigsegv ***************************************************
-
-   Signal handler for hardware exceptions.
-
-*******************************************************************************/
-
+/**
+ * Signal handler for hardware exceptions.
+ */
 void md_signal_handler_sigsegv(int sig, siginfo_t *siginfo, void *_p)
 {
-       ucontext_t     *_uc;
-       mcontext_t     *_mc;
-       u1             *pv;
-       u1             *sp;
-       u1             *ra;
-       u1             *xpc;
-       u1              opc;
-       u1              mod;
-       u1              rm;
-       s4              d;
-       s4              disp;
-       ptrint          val;
-       s4              type;
-       void           *p;
-
-       _uc = (ucontext_t *) _p;
-       _mc = &_uc->uc_mcontext;
-
-       pv  = NULL;                 /* is resolved during stackframeinfo creation */
-       sp  = (u1 *) _mc->gregs[REG_ESP];
-       xpc = (u1 *) _mc->gregs[REG_EIP];
-       ra  = xpc;                              /* return address is equal to XPC */
-
-       /* get exception-throwing instruction */
-
-       opc = M_ALD_MEM_GET_OPC(xpc);
-       mod = M_ALD_MEM_GET_MOD(xpc);
-       rm  = M_ALD_MEM_GET_RM(xpc);
-
-       /* for values see emit_mov_mem_reg and emit_mem */
-
-       if ((opc == 0x8b) && (mod == 0) && (rm == 5)) {
-               /* this was a hardware-exception */
-
-               d    = M_ALD_MEM_GET_REG(xpc);
-               disp = M_ALD_MEM_GET_DISP(xpc);
-
-               /* we use the exception type as load displacement */
-
-               type = disp;
-
-               /* ATTENTION: The _mc->gregs layout is completely crazy!  The
-                  registers are reversed starting with number 4 for REG_EDI
-                  (see /usr/include/sys/ucontext.h).  We have to convert that
-                  here. */
-
-               val = _mc->gregs[REG_EAX - d];
-
-               if (type == TRAP_COMPILER) {
-                       /* The PV from the compiler stub is equal to the XPC. */
-
-                       pv = xpc;
-
-                       /* We use a framesize of zero here because the call pushed
-                          the return addres onto the stack. */
-
-                       ra = md_stacktrace_get_returnaddress(sp, 0);
-
-                       /* Skip the RA on the stack. */
-
-                       sp = sp + 1 * SIZEOF_VOID_P;
-
-                       /* The XPC is the RA minus 2, because the RA points to the
-                          instruction after the call. */
-
-                       xpc = ra - 2;
-               }
-       }
-       else {
-               /* this was a normal NPE */
+       ucontext_t* _uc = (ucontext_t *) _p;
+       mcontext_t* _mc = &_uc->uc_mcontext;
 
-               type = TRAP_NullPointerException;
-               val  = 0;
-       }
+       void* xpc = (void*) _mc->gregs[REG_EIP];
 
-       /* Handle the trap. */
-
-       p = trap_handle(type, val, pv, sp, ra, xpc, _p);
-
-       /* Set registers. */
-
-       if (type == TRAP_COMPILER) {
-               if (p == NULL) {
-                       _mc->gregs[REG_ESP] = (uintptr_t) sp;    /* Remove RA from stack. */
-               }
-       }
+       // Handle the trap.
+       trap_handle(TRAP_SIGSEGV, xpc, _p);
 }
 
 
-/* md_signal_handler_sigfpe ****************************************************
-
-   ArithmeticException signal handler for hardware divide by zero
-   check.
-
-*******************************************************************************/
-
+/**
+ * Signal handler for hardware divide by zero (ArithmeticException)
+ * check.
+ */
 void md_signal_handler_sigfpe(int sig, siginfo_t *siginfo, void *_p)
 {
-       ucontext_t     *_uc;
-       mcontext_t     *_mc;
-       u1             *pv;
-       u1             *sp;
-       u1             *ra;
-       u1             *xpc;
-       s4              type;
-       ptrint          val;
-
-       _uc = (ucontext_t *) _p;
-       _mc = &_uc->uc_mcontext;
-
-       pv  = NULL;                 /* is resolved during stackframeinfo creation */
-       sp  = (u1 *) _mc->gregs[REG_ESP];
-       xpc = (u1 *) _mc->gregs[REG_EIP];
-       ra  = xpc;                          /* return address is equal to xpc     */
-
-       /* This is an ArithmeticException. */
+       ucontext_t* _uc = (ucontext_t *) _p;
+       mcontext_t* _mc = &_uc->uc_mcontext;
 
-       type = TRAP_ArithmeticException;
-       val  = 0;
+       void* xpc = (void*) _mc->gregs[REG_EIP];
 
-       /* Handle the trap. */
-
-       trap_handle(type, val, pv, sp, ra, xpc, _p);
+       // Handle the trap.
+       trap_handle(TRAP_SIGFPE, xpc, _p);
 }
 
 
-/* md_signal_handler_sigill ****************************************************
-
-   Signal handler for hardware patcher traps (ud2).
-
-*******************************************************************************/
-
+/**
+ * Signal handler for hardware patcher traps (ud2).
+ */
 void md_signal_handler_sigill(int sig, siginfo_t *siginfo, void *_p)
 {
-       ucontext_t        *_uc;
-       mcontext_t        *_mc;
-       u1                *pv;
-       u1                *sp;
-       u1                *ra;
-       u1                *xpc;
-       s4                 type;
-       ptrint             val;
-
-       _uc = (ucontext_t *) _p;
-       _mc = &_uc->uc_mcontext;
-
-       pv  = NULL;                 /* is resolved during stackframeinfo creation */
-       sp  = (u1 *) _mc->gregs[REG_ESP];
-       xpc = (u1 *) _mc->gregs[REG_EIP];
-       ra  = xpc;                            /* return address is equal to xpc   */
-
-       // Check if the trap instruction is valid.
-       // TODO Move this into patcher_handler.
-       if (patcher_is_valid_trap_instruction_at(xpc) == false) {
-               // Check if the PC has been patched during our way to this
-               // signal handler (see PR85).
-               if (patcher_is_patched_at(xpc) == true)
-                       return;
-
-               // We have a problem...
-               log_println("md_signal_handler_sigill: Unknown illegal instruction at 0x%lx", xpc);
-#if defined(ENABLE_DISASSEMBLER)
-               (void) disassinstr(xpc);
-#endif
-               vm_abort("Aborting...");
-       }
-
-       type = TRAP_PATCHER;
-       val  = 0;
+       ucontext_t* _uc = (ucontext_t *) _p;
+       mcontext_t* _mc = &_uc->uc_mcontext;
 
-       /* Handle the trap. */
+       void* xpc = (void*) _mc->gregs[REG_EIP];
 
-       trap_handle(type, val, pv, sp, ra, xpc, _p);
+       // Handle the trap.
+       trap_handle(TRAP_SIGILL, xpc, _p);
 }
 
 

diff --git a/src/vm/jit/i386/md-trap.h b/src/vm/jit/i386/md-trap.h
index 52e6a0067ce0d74777e664f73cfc85da4c757e65..6cf2bbf20b99acfa7da6d9c3c28d72758f7d93e3 100644 (file)
--- a/src/vm/jit/i386/md-trap.h
+++ b/src/vm/jit/i386/md-trap.h
@@ -62,6 +62,25 @@ enum {
        TRAP_END
 };
 
+
+/**
+* Macro to fixup a compiler stub.
+* PV : The PV from the compiler stub is equal to the XPC.
+* RA : We use a framesize of zero here because the call pushed
+*      the return addres onto the stack.
+* SP : Skip the RA on the stack.
+* XPC: The XPC is the RA minus 2, because the RA points to the
+*      instruction after the call.
+*/
+#define MD_TRAP_COMPILER_FIXUP(xpc, ra, sp, pv) \
+       do { \
+               (pv)  = (xpc); \
+               (ra)  = md_stacktrace_get_returnaddress((sp), 0); \
+               (sp)  = (void*) (((uintptr_t) (sp)) + 1 * SIZEOF_VOID_P); \
+               (xpc) = (void*) (((uintptr_t) (ra)) - 2); \
+       } while(0)
+
+
 #endif /* _MD_TRAP_H */
 
 

diff --git a/src/vm/jit/i386/md.c b/src/vm/jit/i386/md.c
index 191cddabd02cdb6d88b8b99a1b62b38dd6598c02..4b9a02a431f08fb95362d601bcd4c1c2d75f82c0 100644 (file)
--- a/src/vm/jit/i386/md.c
+++ b/src/vm/jit/i386/md.c
@@ -2,6 +2,7 @@
 
    Copyright (C) 1996-2005, 2006, 2007, 2008
    CACAOVM - Verein zur Foerderung der freien virtuellen Maschine CACAO
+   Copyright (C) 2009 Theobroma Systems Ltd.
 
    This file is part of CACAO.
 
@@ -30,11 +31,14 @@
 
 #include "vm/types.h"
 
+#include "vm/jit/i386/codegen.h"
+
 #include "vm/global.h"
 #include "vm/vm.hpp"
 
 #include "vm/jit/asmpart.h"
 #include "vm/jit/jit.hpp"
+#include "vm/jit/trap.hpp"
 
 
 /* md_init *********************************************************************
@@ -129,6 +133,68 @@ void *md_jit_method_patch_address(void *pv, void *ra, void *mptr)
 }
 
 
+/**
+ * Decode the trap instruction at the given PC.
+ *
+ * @param trp information about trap to be filled
+ * @param sig signal number
+ * @param xpc exception PC
+ * @param es execution state of the machine
+ * @return true if trap was decoded successfully, false otherwise.
+ */
+bool md_trap_decode(trapinfo_t* trp, int sig, void* _xpc, executionstate_t* es)
+{
+       uint8_t* xpc = (uint8_t*) _xpc;
+
+       switch (sig) {
+       case TRAP_SIGFPE:
+               // This is an ArithmeticException.
+               trp->type  = TRAP_ArithmeticException;
+               trp->value = 0;
+               return true;
+
+       case TRAP_SIGILL:
+               // Check for valid trap instruction.
+               if (patcher_is_valid_trap_instruction_at(xpc)) {
+                       trp->type  = TRAP_PATCHER;
+                       trp->value = 0;
+                       return true;
+               }
+               return false;
+
+       case TRAP_SIGSEGV:
+       {
+               // Get exception-throwing instruction.
+               uint8_t opc = M_ALD_MEM_GET_OPC(xpc);
+               uint8_t mod = M_ALD_MEM_GET_MOD(xpc);
+               uint8_t rm  = M_ALD_MEM_GET_RM(xpc);
+
+               // Check for hardware exception, for values
+               // see emit_mov_mem_reg and emit_mem.
+               if ((opc == 0x8b) && (mod == 0) && (rm == 5)) {
+                       int32_t d    = M_ALD_MEM_GET_REG(xpc);
+                       int32_t disp = M_ALD_MEM_GET_DISP(xpc);
+
+                       // We use the exception type as load displacement.
+                       trp->type  = disp;
+                       trp->value = es->intregs[d];
+                       return true;
+               }
+
+               // Default case is a normal NullPointerException.
+               else {
+                       trp->type  = TRAP_NullPointerException;
+                       trp->value = 0;
+                       return true;
+               }
+       }
+
+       default:
+               return false;
+       }
+}
+
+
 /* md_patch_replacement_point **************************************************
 
    Patch the given replacement point.

diff --git a/src/vm/jit/trap.cpp b/src/vm/jit/trap.cpp
index 3f77c9746e90b59ce5b2b6ef4187dcd356595889..3f95aaa90909159728f7a127770d60a3037940f4 100644 (file)
--- a/src/vm/jit/trap.cpp
+++ b/src/vm/jit/trap.cpp
@@ -271,7 +271,7 @@ void trap_handle(int sig, void *xpc, void *context)
 #if defined(ENABLE_REPLACEMENT)
        case TRAP_COUNTDOWN:
 # if defined(__I386__)
-               replace_me_wrapper((char*)xpc - 13, context);
+               replace_me_wrapper((uint8_t*) xpc - 13, context);
 # endif
                p = NULL;
                break;