+2000-07-10 Elena Zannoni <ezannoni@kwikemart.cygnus.com>
+
+ * config/sh/tm-sh.h (STORE_RETURN_VALUE): Redefine as
+ sh_store_return_value().
+ * sh-tdep.c (sh_store_return_value): New function. Store the
+ value returned by a function into the appropriate register.
+
+2000-07-10 Elena Zannoni <ezannoni@kwikemart.cygnus.com>
+
+ * sh-tdep.c (sh_skip_prologue): Before looking at the actual
+ instructions, try to see if the symbol table can be of help, by
+ calling after_prologue(). If this doesn't work, call
+ skip_prologue_hard_way().
+ (skip_prologue_hard_way): Renamed from sh_skip_prologue. Add some
+ more instruction pattern matching for pushing of arguments, and
+ manipulation of r14.
+ (after_prologue): New function. Use symbol table info to determine
+ the end of the prologue, if possible.
+
2000-07-07 Michael Snyder <msnyder@cleaver.cygnus.com>
* findvar.c (_initialize_findvar, build_findvar, write_fp, read_fp,
[sts.l pr,@-r15]
[mov.l r14,@-r15]
[mov r15,r14]
+
+ Actually it can be more complicated than this. For instance, with
+ newer gcc's:
+
+ mov.l r14,@-r15
+ add #-12,r15
+ mov r15,r14
+ mov r4,r1
+ mov r5,r2
+ mov.l r6,@(4,r14)
+ mov.l r7,@(8,r14)
+ mov.b r1,@r14
+ mov r14,r1
+ mov r14,r1
+ add #2,r1
+ mov.w r2,@r1
+
*/
+/* STS.L PR,@-r15 0100111100100010
+ r15-4-->r15, PR-->(r15) */
#define IS_STS(x) ((x) == 0x4f22)
+
+/* MOV.L Rm,@-r15 00101111mmmm0110
+ r15-4-->r15, Rm-->(R15) */
#define IS_PUSH(x) (((x) & 0xff0f) == 0x2f06)
+
#define GET_PUSHED_REG(x) (((x) >> 4) & 0xf)
+
+/* MOV r15,r14 0110111011110011
+ r15-->r14 */
#define IS_MOV_SP_FP(x) ((x) == 0x6ef3)
+
+/* ADD #imm,r15 01111111iiiiiiii
+ r15+imm-->r15 */
#define IS_ADD_SP(x) (((x) & 0xff00) == 0x7f00)
+
#define IS_MOV_R3(x) (((x) & 0xff00) == 0x1a00)
#define IS_SHLL_R3(x) ((x) == 0x4300)
+
+/* ADD r3,r15 0011111100111100
+ r15+r3-->r15 */
#define IS_ADD_R3SP(x) ((x) == 0x3f3c)
+
+/* FMOV.S FRm,@-Rn Rn-4-->Rn, FRm-->(Rn) 1111nnnnmmmm1011
+ or
+ FMOV DRm,@-Rn Rn-8-->Rn, DRm-->(Rn) 1111nnnnmmm01011
+ or
+ FMOV XDm,@-Rn Rn-8-->Rn, XDm-->(Rn) 1111nnnnmmm11011 */
#define IS_FMOV(x) (((x) & 0xf00f) == 0xf00b)
-#define FPSCR_SZ (1 << 20)
+/* MOV Rm,Rn Rm-->Rn 0110nnnnmmmm0011
+ or
+ MOV.L Rm,@(disp,Rn) Rm-->(dispx4+Rn) 0001nnnnmmmmdddd
+ or
+ MOV.L Rm,@Rn Rm-->(Rn) 0010nnnnmmmm0010
+ where Rm is one of r4,r5,r6,r7 which are the argument registers. */
+#define IS_ARG_MOV(x) \
+(((((x) & 0xf00f) == 0x6003) && (((x) & 0x00f0) >= 0x0040 && ((x) & 0x00f0) <= 0x0070)) \
+|| ((((x) & 0xf000) == 0x1000) && (((x) & 0x00f0) >= 0x0040 && ((x) & 0x00f0) <= 0x0070)) \
+|| ((((x) & 0xf00f) == 0x2002) && (((x) & 0x00f0) >= 0x0040 && ((x) & 0x00f0) <= 0x0070)))
+
+/* MOV.L Rm,@(disp,r14) 00011110mmmmdddd
+ Rm-->(dispx4+r14) where Rm is one of r4,r5,r6,r7 */
+#define IS_MOV_R14(x) \
+((((x) & 0xff00) == 0x1e) && (((x) & 0x00f0) >= 0x0040 && ((x) & 0x00f0) <= 0x0070))
+
+#define FPSCR_SZ (1 << 20)
/* Should call_function allocate stack space for a struct return? */
int
return (TYPE_LENGTH (type) > 1);
}
-
/* Skip any prologue before the guts of a function */
-CORE_ADDR
-sh_skip_prologue (start_pc)
+/* Skip the prologue using the debug information. If this fails we'll
+ fall back on the 'guess' method below. */
+static CORE_ADDR
+after_prologue (pc)
+ CORE_ADDR pc;
+{
+ struct symtab_and_line sal;
+ CORE_ADDR func_addr, func_end;
+
+ /* If we can not find the symbol in the partial symbol table, then
+ there is no hope we can determine the function's start address
+ with this code. */
+ if (!find_pc_partial_function (pc, NULL, &func_addr, &func_end))
+ return 0;
+
+ /* Get the line associated with FUNC_ADDR. */
+ sal = find_pc_line (func_addr, 0);
+
+ /* There are only two cases to consider. First, the end of the source line
+ is within the function bounds. In that case we return the end of the
+ source line. Second is the end of the source line extends beyond the
+ bounds of the current function. We need to use the slow code to
+ examine instructions in that case. */
+ if (sal.end < func_end)
+ return sal.end;
+ else
+ return 0;
+}
+
+/* Here we look at each instruction in the function, and try to guess
+ where the prologue ends. Unfortunately this is not always
+ accurate. */
+static CORE_ADDR
+skip_prologue_hard_way (start_pc)
CORE_ADDR start_pc;
{
CORE_ADDR here, end;
+ int updated_fp = 0;
if (!start_pc)
return 0;
int w = read_memory_integer (here, 2);
here += 2;
if (IS_FMOV (w) || IS_PUSH (w) || IS_STS (w) || IS_MOV_R3 (w)
- || IS_ADD_R3SP (w) || IS_ADD_SP (w) || IS_SHLL_R3 (w))
- start_pc = here;
-
- if (IS_MOV_SP_FP (w))
+ || IS_ADD_R3SP (w) || IS_ADD_SP (w) || IS_SHLL_R3 (w)
+ || IS_ARG_MOV (w) || IS_MOV_R14 (w))
{
start_pc = here;
- break;
}
+ else if (IS_MOV_SP_FP (w))
+ {
+ start_pc = here;
+ updated_fp = 1;
+ }
+ else
+ /* Don't bail out yet, if we are before the copy of sp. */
+ if (updated_fp)
+ break;
}
return start_pc;
}
+CORE_ADDR
+sh_skip_prologue (pc)
+ CORE_ADDR pc;
+{
+ CORE_ADDR post_prologue_pc;
+
+ /* See if we can determine the end of the prologue via the symbol table.
+ If so, then return either PC, or the PC after the prologue, whichever
+ is greater. */
+
+ post_prologue_pc = after_prologue (pc);
+
+ /* If after_prologue returned a useful address, then use it. Else
+ fall back on the instruction skipping code. */
+ if (post_prologue_pc != 0)
+ return max (pc, post_prologue_pc);
+ else
+ return (skip_prologue_hard_way (pc));
+}
+
/* Disassemble an instruction. */
int
error ("bad size for return value");
}
+/* If the architecture is sh4 or sh3e, store a function's return value
+ in the R0 general register or in the FP0 floating point register,
+ depending on the type of the return value. In all the other cases
+ the result is stored in r0. */
+void
+sh_store_return_value (struct type *type, void *valbuf)
+{
+ int cpu;
+ if (TARGET_ARCHITECTURE->arch == bfd_arch_sh)
+ cpu = TARGET_ARCHITECTURE->mach;
+ else
+ cpu = 0;
+ if (cpu == bfd_mach_sh3e || cpu == bfd_mach_sh4)
+ {
+ if (TYPE_CODE (type) == TYPE_CODE_FLT)
+ write_register_bytes (REGISTER_BYTE (FP0_REGNUM), valbuf, TYPE_LENGTH (type));
+ else
+ write_register_bytes (REGISTER_BYTE (0), valbuf, TYPE_LENGTH (type));
+ }
+ else
+ write_register_bytes (REGISTER_BYTE (0), valbuf, TYPE_LENGTH (type));
+}
+
void
_initialize_sh_tdep ()
{
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