/* GNU/Linux on ARM target support.
- Copyright 1999, 2000 Free Software Foundation, Inc.
+ Copyright 1999, 2000, 2001 Free Software Foundation, Inc.
This file is part of GDB.
#include "value.h"
#include "gdbtypes.h"
#include "floatformat.h"
+#include "gdbcore.h"
+#include "frame.h"
+#include "regcache.h"
+#include "doublest.h"
/* For arm_linux_skip_solib_resolver. */
#include "symtab.h"
#define UNMAKE_THUMB_ADDR(addr) ((addr) & ~1)
CORE_ADDR
-arm_linux_push_arguments (int nargs, value_ptr * args, CORE_ADDR sp,
+arm_linux_push_arguments (int nargs, struct value **args, CORE_ADDR sp,
int struct_return, CORE_ADDR struct_addr)
{
char *fp;
{
int len;
char *val;
- double dbl_arg;
CORE_ADDR regval;
enum type_code typecode;
struct type *arg_type, *target_type;
calling the function. */
if (TYPE_CODE_FLT == typecode && REGISTER_SIZE == len)
{
- /* Float argument in buffer is in host format. Read it and
- convert to DOUBLEST, and store it in target double. */
DOUBLEST dblval;
-
+ dblval = extract_floating (val, len);
len = TARGET_DOUBLE_BIT / TARGET_CHAR_BIT;
- floatformat_to_doublest (HOST_FLOAT_FORMAT, val, &dblval);
- store_floating (&dbl_arg, len, dblval);
- val = (char *) &dbl_arg;
+ val = alloca (len);
+ store_floating (val, len, dblval);
}
/* If the argument is a pointer to a function, and it is a Thumb
if (resolver)
{
struct minimal_symbol *fixup
- = lookup_minimal_symbol ("fixup", 0, objfile);
+ = lookup_minimal_symbol ("fixup", NULL, objfile);
if (fixup && SYMBOL_VALUE_ADDRESS (fixup) == pc)
return (SAVED_PC_AFTER_CALL (get_current_frame ()));
/* Plug in functions for other kinds of resolvers here. */
result = skip_hurd_resolver (pc);
- printf ("Result = 0x%08x\n");
+
if (result)
return result;
-
return 0;
}
+/* The constants below were determined by examining the following files
+ in the linux kernel sources:
+
+ arch/arm/kernel/signal.c
+ - see SWI_SYS_SIGRETURN and SWI_SYS_RT_SIGRETURN
+ include/asm-arm/unistd.h
+ - see __NR_sigreturn, __NR_rt_sigreturn, and __NR_SYSCALL_BASE */
+
+#define ARM_LINUX_SIGRETURN_INSTR 0xef900077
+#define ARM_LINUX_RT_SIGRETURN_INSTR 0xef9000ad
+
+/* arm_linux_in_sigtramp determines if PC points at one of the
+ instructions which cause control to return to the Linux kernel upon
+ return from a signal handler. FUNC_NAME is unused. */
+
+int
+arm_linux_in_sigtramp (CORE_ADDR pc, char *func_name)
+{
+ unsigned long inst;
+
+ inst = read_memory_integer (pc, 4);
+
+ return (inst == ARM_LINUX_SIGRETURN_INSTR
+ || inst == ARM_LINUX_RT_SIGRETURN_INSTR);
+
+}
+
+/* arm_linux_sigcontext_register_address returns the address in the
+ sigcontext of register REGNO given a stack pointer value SP and
+ program counter value PC. The value 0 is returned if PC is not
+ pointing at one of the signal return instructions or if REGNO is
+ not saved in the sigcontext struct. */
+
+CORE_ADDR
+arm_linux_sigcontext_register_address (CORE_ADDR sp, CORE_ADDR pc, int regno)
+{
+ unsigned long inst;
+ CORE_ADDR reg_addr = 0;
+
+ inst = read_memory_integer (pc, 4);
+
+ if (inst == ARM_LINUX_SIGRETURN_INSTR || inst == ARM_LINUX_RT_SIGRETURN_INSTR)
+ {
+ CORE_ADDR sigcontext_addr;
+
+ /* The sigcontext structure is at different places for the two
+ signal return instructions. For ARM_LINUX_SIGRETURN_INSTR,
+ it starts at the SP value. For ARM_LINUX_RT_SIGRETURN_INSTR,
+ it is at SP+8. For the latter instruction, it may also be
+ the case that the address of this structure may be determined
+ by reading the 4 bytes at SP, but I'm not convinced this is
+ reliable.
+
+ In any event, these magic constants (0 and 8) may be
+ determined by examining struct sigframe and struct
+ rt_sigframe in arch/arm/kernel/signal.c in the Linux kernel
+ sources. */
+
+ if (inst == ARM_LINUX_RT_SIGRETURN_INSTR)
+ sigcontext_addr = sp + 8;
+ else /* inst == ARM_LINUX_SIGRETURN_INSTR */
+ sigcontext_addr = sp + 0;
+
+ /* The layout of the sigcontext structure for ARM GNU/Linux is
+ in include/asm-arm/sigcontext.h in the Linux kernel sources.
+
+ There are three 4-byte fields which precede the saved r0
+ field. (This accounts for the 12 in the code below.) The
+ sixteen registers (4 bytes per field) follow in order. The
+ PSR value follows the sixteen registers which accounts for
+ the constant 19 below. */
+
+ if (0 <= regno && regno <= PC_REGNUM)
+ reg_addr = sigcontext_addr + 12 + (4 * regno);
+ else if (regno == PS_REGNUM)
+ reg_addr = sigcontext_addr + 19 * 4;
+ }
+
+ return reg_addr;
+}
+
void
_initialize_arm_linux_tdep (void)
{
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