#include "recog.h"
#include "expr.h"
#include "obstack.h"
+#include "tree.h"
+
+extern char *language_string;
#define min(A,B) ((A) < (B) ? (A) : (B))
#define max(A,B) ((A) > (B) ? (A) : (B))
fprintf (file, "\tbr\n");
}
- /* ??? Need to output a traceback table here when -g was given for complete
- debugging output. */
+ /* Output a traceback table here. See /usr/include/sys/debug.h for info
+ on its format. */
+ {
+ char *fname = XSTR (XEXP (DECL_RTL (current_function_decl), 0), 0);
+ int fixed_parms, float_parms, parm_info;
+ int i;
+
+ /* Need label immediately before tbtab, so we can compute its offset
+ from the function start. */
+ if (*fname == '*')
+ ++fname;
+ fprintf (file, "L..tbtab_");
+ ASM_OUTPUT_LABEL (file, fname);
+
+ /* The .tbtab psuedo-op can only be used for the first eight
+ expressions, since it can't handle the possibly variable length
+ fields that follow. However, if you omit the optional fields,
+ the assembler outputs zeros for all optional fields anyways, giving each
+ variable length field is minimum length (as defined in sys/debug.h).
+ Thus we can not use the .tbtab psuedo-op at all. */
+
+ /* An all-zero word flags the start of the tbtab, for debuggers that have
+ to find it by searching forward from the entry point or from the
+ current pc. */
+ fprintf (file, "\t.long 0\n");
+
+ /* Tbtab format type. Use format type 0. */
+ fprintf (file, "\t.byte 0\n");
+
+ /* Language type. Unfortunately, there doesn't seem to be any official way
+ to get this info, so we use language_string. C is 0. C++ is 9.
+ No number defined for Obj-C, but it doesn't have its own
+ language_string, so we can't detect it anyways. */
+ if (! strcmp (language_string, "GNU C"))
+ i = 0;
+ else if (! strcmp (language_string, "GNU C++"))
+ i = 9;
+ else
+ abort ();
+ fprintf (file, "\t.byte %d\n", i);
+
+ /* 8 single bit fields: global linkage (not set for C extern linkage,
+ apparently a PL/I convention?), out-of-line epilogue/prologue, offset
+ from start of procedure stored in tbtab, internal function, function
+ has controlled storage, function has no toc, function uses fp,
+ function logs/aborts fp operations. */
+ /* Assume that fp operations are used if any fp reg must be saved. */
+ fprintf (file, "\t.byte %d\n", (1 << 5) | ((first_fp_reg != 64) << 1));
+
+ /* 6 bitfields: function is interrupt handler, name present in proc table,
+ function calls alloca, on condition directives (controls stack walks,
+ 3 bits), saves condition reg, saves link reg. */
+ /* The `function calls alloca' bit seems to be set whenever reg 31 is
+ set up as a frame pointer, even when there is no alloca call. */
+ fprintf (file, "\t.byte %d\n",
+ ((1 << 6) | (frame_pointer_needed << 5)
+ | (must_save_cr () << 1) | (regs_ever_live[65])));
+
+ /* 3 bitfields: saves backchain, spare bit, number of fpr saved
+ (6 bits). */
+ fprintf (file, "\t.byte %d\n",
+ (must_push << 7) | (64 - first_fp_reg_to_save ()));
+
+ /* 2 bitfields: spare bits (2 bits), number of gpr saved (6 bits). */
+ fprintf (file, "\t.byte %d\n", (32 - first_reg_to_save ()));
+
+ {
+ /* Compute the parameter info from the function decl argument list. */
+ tree decl;
+ int next_parm_info_bit;
+
+ next_parm_info_bit = 31;
+ parm_info = 0;
+ fixed_parms = 0;
+ float_parms = 0;
+
+ for (decl = DECL_ARGUMENTS (current_function_decl);
+ decl; decl = TREE_CHAIN (decl))
+ {
+ rtx parameter = DECL_INCOMING_RTL (decl);
+ enum machine_mode mode = GET_MODE (parameter);
+
+ if (GET_CODE (parameter) == REG)
+ {
+ if (GET_MODE_CLASS (mode) == MODE_FLOAT)
+ {
+ int bits;
+
+ float_parms++;
+
+ if (mode == SFmode)
+ bits = 0x2;
+ else if (mode == DFmode)
+ bits = 0x3;
+ else
+ abort ();
+
+ /* If only one bit will fit, don't or in this entry. */
+ if (next_parm_info_bit > 0)
+ parm_info |= (bits << (next_parm_info_bit - 1));
+ next_parm_info_bit -= 2;
+ }
+ else
+ {
+ fixed_parms += ((GET_MODE_SIZE (mode) + (UNITS_PER_WORD - 1))
+ / UNITS_PER_WORD);
+ next_parm_info_bit -= 1;
+ }
+ }
+ }
+ }
+
+ /* Number of fixed point parameters. */
+ /* This is actually the number of words of fixed point parameters; thus
+ an 8 byte struct counts as 2; and thus the maximum value is 8. */
+ fprintf (file, "\t.byte %d\n", fixed_parms);
+
+ /* 2 bitfields: number of floating point parameters (7 bits), parameters
+ all on stack. */
+ /* This is actually the number of fp registers that hold parameters;
+ and thus the maximum value is 13. */
+ /* Set parameters on stack bit if parameters are not in their original
+ registers, irregardless of whether they are on the stack? Xlc
+ seems to set the bit when not optimizing. */
+ fprintf (file, "\t.byte %d\n", ((float_parms << 1) | (! optimize)));
+
+ /* Optional fields follow. Some are variable length. */
+
+ /* Parameter types, left adjusted bit fields: 0 fixed, 10 single float,
+ 11 double float. */
+ /* There is an entry for each parameter in a register, in the order that
+ they occur in the parameter list. Any intervening arguments on the
+ stack are ignored. If the list overflows a long (max possible length
+ 34 bits) then completely leave off all elements that don't fit. */
+ /* Only emit this long if there was at least one parameter. */
+ if (fixed_parms || float_parms)
+ fprintf (file, "\t.long %d\n", parm_info);
+
+ /* Offset from start of code to tb table. */
+ fprintf (file, "\t.long L..tbtab_");
+ RS6000_OUTPUT_BASENAME (file, fname);
+ fprintf (file, "-.");
+ RS6000_OUTPUT_BASENAME (file, fname);
+ fprintf (file, "\n");
+
+ /* Interrupt handler mask. */
+ /* Omit this long, since we never set the iterrupt handler bit above. */
+
+ /* Number of CTL (controlled storage) anchors. */
+ /* Omit this long, since the has_ctl bit is never set above. */
+
+ /* Displacement into stack of each CTL anchor. */
+ /* Omit this list of longs, because there are no CTL anchors. */
+
+ /* Length of function name. */
+ fprintf (file, "\t.short %d\n", strlen (fname));
+
+ /* Function name. */
+ assemble_string (fname, strlen (fname));
+
+ /* Register for alloca automatic storage; this is always reg 31.
+ Only emit this if the alloca bit was set above. */
+ if (frame_pointer_needed)
+ fprintf (file, "\t.byte 31\n");
+ }
}
\f
/* Output a TOC entry. We derive the entry name from what is
projects / gcc.git / commitdiff