* src/vm/jit/trap.cpp (trap_handle): Further generalized trap handling and

[cacao.git] / src / vm / jit / x86_64 / md.c

diff --git a/src/vm/jit/x86_64/md.c b/src/vm/jit/x86_64/md.c
index 586550cfd485340406a80c301f65564c815e50f2..cf682e09f76b387c7814716abf7124b776596774 100644 (file)
--- a/src/vm/jit/x86_64/md.c
+++ b/src/vm/jit/x86_64/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.
 
@@ -29,12 +30,15 @@
 #include <stdint.h>
 #include <stdlib.h>
 
+#include "vm/jit/x86_64/codegen.h"
 #include "vm/jit/x86_64/md-abi.h"
 
 #include "vm/vm.hpp"
 
 #include "vm/jit/codegen-common.hpp"
+#include "vm/jit/executionstate.h"
 #include "vm/jit/jit.hpp"
+#include "vm/jit/trap.hpp"
 
 
 /* md_init *********************************************************************
@@ -135,6 +139,73 @@ 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;
+
+#if 0
+       // Check for StackOverflowException.
+       threads_check_stackoverflow(sp);
+#endif
+
+       switch (sig) {
+       case TRAP_SIGFPE:
+               // Check for 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 == 4)) {
+                       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.