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- /* Output variables, constants and external declarations, for GNU compiler.
- Copyright (C) 1987, 1988, 1989 Free Software Foundation, Inc.
-
- This file is part of GNU CC.
-
- GNU CC is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 1, or (at your option)
- any later version.
-
- GNU CC is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with GNU CC; see the file COPYING. If not, write to
- the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
-
-
- /* This file handles generation of all the assembler code
- *except* the instructions of a function.
- This includes declarations of variables and their initial values.
-
- We also output the assembler code for constants stored in memory
- and are responsible for combining constants with the same value. */
-
- #include <stdio.h>
- #include <setjmp.h>
- /* #include <stab.h> */
- #include "config.h"
- #include "rtl.h"
- #include "tree.h"
- #include "flags.h"
- #include "expr.h"
- #include "hard-reg-set.h"
-
- #include "obstack.h"
-
- #define MIN(a, b) ((a) < (b) ? (a) : (b))
-
- /* File in which assembler code is being written. */
-
- extern FILE *asm_out_file;
-
- /* The (assembler) name of the first globally-visible object output. */
- char *first_global_object_name = 0;
-
- extern struct obstack *current_obstack;
- extern struct obstack *saveable_obstack;
- extern struct obstack permanent_obstack;
- #define obstack_chunk_alloc xmalloc
- extern int xmalloc ();
-
- /* Number for making the label on the next
- constant that is stored in memory. */
-
- int const_labelno;
-
- /* Number for making the label on the next
- static variable internal to a function. */
-
- int var_labelno;
-
- /* Nonzero if at least one function definition has been seen. */
- static int function_defined;
-
- extern FILE *asm_out_file;
-
- static char *compare_constant_1 ();
- static void record_constant_1 ();
- void output_constant_pool ();
- void assemble_name ();
- void output_addressed_constants ();
- void output_constant ();
- void output_constructor ();
-
- #ifdef EXTRA_SECTIONS
- static enum in_section {no_section, in_text, in_data, EXTRA_SECTIONS} in_section
- = no_section;
- #else
- static enum in_section {no_section, in_text, in_data} in_section
- = no_section;
- #endif
-
- /* Define functions like text_section for any extra sections. */
- #ifdef EXTRA_SECTION_FUNCTIONS
- EXTRA_SECTION_FUNCTIONS
- #endif
-
- /* Tell assembler to switch to text section. */
-
- void
- text_section ()
- {
- if (in_section != in_text)
- {
- fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
- in_section = in_text;
- }
- }
-
- /* Tell assembler to switch to data section. */
-
- void
- data_section ()
- {
- if (in_section != in_data)
- {
- if (flag_shared_data)
- {
- #ifdef SHARED_SECTION_ASM_OP
- fprintf (asm_out_file, "%s\n", SHARED_SECTION_ASM_OP);
- #else
- fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
- #endif
- }
- else
- fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
-
- in_section = in_data;
- }
- }
-
- /* Determine if we're in the text section. */
-
- int
- in_text_section ()
- {
- return in_section == in_text;
- }
-
- /* Create the rtl to represent a function, for a function definition.
- DECL is a FUNCTION_DECL node which describes which function.
- The rtl is stored into DECL. */
-
- void
- make_function_rtl (decl)
- tree decl;
- {
- /* Rename a nested function to avoid conflicts. */
- if (DECL_CONTEXT (decl) != 0 && DECL_INITIAL (decl) != 0
- && DECL_RTL (decl) == 0)
- {
- char *name = IDENTIFIER_POINTER (DECL_NAME (decl));
- char *label;
-
- ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno);
- DECL_ASSEMBLER_NAME (decl)
- = obstack_copy0 (saveable_obstack, label, strlen (label));
- var_labelno++;
- }
-
- if (DECL_RTL (decl) == 0)
- DECL_RTL (decl)
- = gen_rtx (MEM, DECL_MODE (decl),
- gen_rtx (SYMBOL_REF, Pmode, DECL_ASSEMBLER_NAME (decl)));
-
- /* Record at least one function has been defined. */
- function_defined = 1;
- }
-
- /* Decode an `asm' spec for a declaration as a register name.
- Return the register number, or -1 if nothing specified,
- or -2 if the name is not a register. */
-
- int
- decode_reg_name (asmspec)
- char *asmspec;
- {
- if (asmspec != 0)
- {
- int i;
- extern char *reg_names[];
-
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (!strcmp (asmspec, reg_names[i]))
- break;
-
- if (i < FIRST_PSEUDO_REGISTER)
- return i;
- else
- return -2;
- }
-
- return -1;
- }
-
- /* Create the DECL_RTL for a declaration for a static or external variable
- or static or external function.
- ASMSPEC, if not 0, is the string which the user specified
- as the assembler symbol name.
- TOP_LEVEL is nonzero if this is a file-scope variable.
-
- This is never called for PARM_DECL nodes. */
-
- void
- make_decl_rtl (decl, asmspec, top_level)
- tree decl;
- char *asmspec;
- int top_level;
- {
- register char *name = DECL_ASSEMBLER_NAME (decl);
- int reg_number = decode_reg_name (asmspec);
-
- if (reg_number == -2)
- {
- name = (char *) obstack_alloc (saveable_obstack,
- strlen (asmspec) + 2);
- name[0] = '*';
- strcpy (&name[1], asmspec);
- }
-
- /* For a duplicate declaration, we can be called twice on the
- same DECL node. Don't alter the RTL already made
- unless the old mode is wrong (which can happen when
- the previous rtl was made when the type was incomplete). */
- if (DECL_RTL (decl) == 0
- || GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl))
- {
- DECL_RTL (decl) = 0;
-
- /* First detect errors in declaring global registers. */
- if (TREE_REGDECL (decl) && reg_number == -1)
- error_with_decl (decl,
- "register name not specified for `%s'");
- else if (TREE_REGDECL (decl) && reg_number == -2)
- error_with_decl (decl,
- "invalid register name for `%s'");
- else if (reg_number >= 0 && ! TREE_REGDECL (decl))
- error_with_decl (decl,
- "register name given for non-register variable `%s'");
- else if (TREE_REGDECL (decl) && TREE_CODE (decl) == FUNCTION_DECL)
- error ("function declared `register'");
- else if (TREE_REGDECL (decl) && TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
- error_with_decl (decl, "data type of `%s' isn't suitable for a register");
- /* Now handle properly declared static register variables. */
- else if (TREE_REGDECL (decl))
- {
- int nregs;
- if (pedantic)
- warning ("ANSI C forbids global register variables");
- if (DECL_INITIAL (decl) != 0)
- {
- DECL_INITIAL (decl) = 0;
- error ("global register variable has initial value");
- }
- if (fixed_regs[reg_number] == 0
- && function_defined && top_level)
- error ("global register variable follows a function definition");
- if (TREE_THIS_VOLATILE (decl))
- warning ("volatile register variables don't work as you might wish");
- DECL_RTL (decl) = gen_rtx (REG, DECL_MODE (decl), reg_number);
- if (top_level)
- {
- /* Make this register fixed, so not usable for anything else. */
- nregs = HARD_REGNO_NREGS (reg_number, DECL_MODE (decl));
- while (nregs > 0)
- global_regs[reg_number + --nregs] = 1;
- init_reg_sets_1 ();
- }
- }
-
- /* Now handle ordinary static variables and functions (in memory).
- Also handle vars declared register invalidly. */
- if (DECL_RTL (decl) == 0)
- {
- /* Can't use just the variable's own name for a variable
- whose scope is less than the whole file.
- Concatenate a distinguishing number. */
- if (!top_level && !TREE_EXTERNAL (decl) && asmspec == 0)
- {
- char *label;
-
- ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno);
- name = obstack_copy0 (saveable_obstack, label, strlen (label));
- var_labelno++;
- }
-
- DECL_RTL (decl) = gen_rtx (MEM, DECL_MODE (decl),
- gen_rtx (SYMBOL_REF, Pmode, name));
- if (TREE_VOLATILE (decl))
- MEM_VOLATILE_P (DECL_RTL (decl)) = 1;
- if (TREE_READONLY (decl))
- RTX_UNCHANGING_P (DECL_RTL (decl)) = 1;
- MEM_IN_STRUCT_P (DECL_RTL (decl))
- = (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
- || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
- || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE);
- }
- }
- }
-
- /* Output a string of literal assembler code
- for an `asm' keyword used between functions. */
-
- void
- assemble_asm (string)
- tree string;
- {
- app_enable ();
-
- fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
- }
-
- /* Output assembler code for the constant pool of a function and associated
- with defining the name of the function. DECL describes the function.
- For the constant pool, we use the current constant pool data. */
-
- void
- assemble_function (decl)
- tree decl;
- {
- rtx x, n;
- char *fnname;
- int align;
-
- /* Get the function's name, as described by its RTL.
- This may be different from the DECL_NAME name used in the source file. */
-
- x = DECL_RTL (decl);
- if (GET_CODE (x) != MEM)
- abort ();
- n = XEXP (x, 0);
- if (GET_CODE (n) != SYMBOL_REF)
- abort ();
- fnname = XSTR (n, 0);
-
- /* The following code does not need preprocessing in the assembler. */
-
- app_disable ();
-
- output_constant_pool (fnname, decl);
-
- text_section ();
-
- #ifdef SDB_DEBUGGING_INFO
- /* Make sure types are defined for debugger before fcn name is defined. */
- if (write_symbols == SDB_DEBUG)
- sdbout_tags (gettags ());
- #endif
-
- /* Tell assembler to move to target machine's alignment for functions. */
-
- align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
- if (align > 0)
- ASM_OUTPUT_ALIGN (asm_out_file, align);
-
- #ifdef SDB_DEBUGGING_INFO
- /* Output SDB definition of the function. */
- if (write_symbols == SDB_DEBUG)
- sdbout_mark_begin_function ();
- #endif
-
- /* Make function name accessible from other files, if appropriate. */
-
- if (TREE_PUBLIC (decl))
- {
- if (!first_global_object_name)
- first_global_object_name = fnname;
- ASM_GLOBALIZE_LABEL (asm_out_file, fnname);
- }
-
- /* Do any machine/system dependent processing of the function name */
- #ifdef ASM_DECLARE_FUNCTION_NAME
- ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
- #else
- /* Standard thing is just output label for the function. */
- ASM_OUTPUT_LABEL (asm_out_file, fnname);
- #endif /* ASM_DECLARE_FUNCTION_NAME */
- }
-
- /* Assemble " .int 0\n" or whatever this assembler wants. */
-
- void
- assemble_integer_zero ()
- {
- ASM_OUTPUT_INT (asm_out_file, const0_rtx);
- }
-
- /* Assemble a string constant with the specified C string as contents. */
-
- void
- assemble_string (p, size)
- unsigned char *p;
- int size;
- {
- register int i;
- int pos = 0;
- int maximum = 2000;
-
- /* If the string is very long, split it up. */
-
- while (pos < size)
- {
- int thissize = size - pos;
- if (thissize > maximum)
- thissize = maximum;
-
- #ifdef ASM_OUTPUT_ASCII
- ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
- #else
- fprintf (asm_out_file, "\t.ascii \"");
-
- for (i = 0; i < thissize; i++)
- {
- register int c = p[i];
- if (c == '\"' || c == '\\')
- putc ('\\', asm_out_file);
- if (c >= ' ' && c < 0177)
- putc (c, asm_out_file);
- else
- {
- fprintf (asm_out_file, "\\%o", c);
- /* After an octal-escape, if a digit follows,
- terminate one string constant and start another.
- The Vax assembler fails to stop reading the escape
- after three digits, so this is the only way we
- can get it to parse the data properly. */
- if (i < thissize - 1
- && p[i + 1] >= '0' && p[i + 1] <= '9')
- fprintf (asm_out_file, "\"\n\t.ascii \"");
- }
- }
- fprintf (asm_out_file, "\"\n");
- #endif /* no ASM_OUTPUT_ASCII */
-
- pos += thissize;
- p += thissize;
- }
- }
-
- /* Assemble everything that is needed for a variable or function declaration.
- Not used for automatic variables, and not used for function definitions.
- Should not be called for variables of incomplete structure type.
-
- TOP_LEVEL is nonzero if this variable has file scope.
- WRITE_SYMBOLS is DBX_DEBUG if writing dbx symbol output.
- The dbx data for a file-scope variable is written here.
- AT_END is nonzero if this is the special handling, at end of compilation,
- to define things that have had only tentative definitions. */
-
- void
- assemble_variable (decl, top_level, write_symbols, at_end)
- tree decl;
- int top_level;
- enum debugger write_symbols;
- int at_end;
- {
- register char *name;
- register int i;
- int align;
-
- /* Do nothing for global register variables. */
-
- if (GET_CODE (DECL_RTL (decl)) == REG)
- return;
-
- /* Normally no need to say anything for external references,
- since assembler considers all undefined symbols external. */
-
- if (TREE_EXTERNAL (decl))
- return;
-
- /* Output no assembler code for a function declaration.
- Only definitions of functions output anything. */
-
- if (TREE_CODE (decl) == FUNCTION_DECL)
- return;
-
- /* If type was incomplete when the variable was declared,
- see if it is complete now. */
-
- if (DECL_SIZE (decl) == 0)
- layout_decl (decl, 0);
-
- /* Still incomplete => don't allocate it; treat the tentative defn
- (which is what it must have been) as an `extern' reference. */
-
- if (DECL_SIZE (decl) == 0)
- {
- error_with_file_and_line (DECL_SOURCE_FILE (decl),
- DECL_SOURCE_LINE (decl),
- "storage size of static var `%s' isn't known",
- IDENTIFIER_POINTER (DECL_NAME (decl)));
- return;
- }
-
- /* The first declaration of a variable that comes through this function
- decides whether it is global (in C, has external linkage)
- or local (in C, has internal linkage). So do nothing more
- if this function has already run. */
-
- if (TREE_ASM_WRITTEN (decl))
- return;
-
- TREE_ASM_WRITTEN (decl) = 1;
-
- #ifdef DBX_DEBUGGING_INFO
- /* File-scope global variables are output here. */
- if (write_symbols == DBX_DEBUG && top_level)
- dbxout_symbol (decl, 0);
- #endif
- #ifdef SDB_DEBUGGING_INFO
- if (write_symbols == SDB_DEBUG && top_level)
- sdbout_symbol (decl, 0);
- #endif
- if (write_symbols == GDB_DEBUG)
- /* Make sure the file is known to GDB even if it has no functions. */
- set_current_gdbfile (DECL_SOURCE_FILE (decl));
-
- /* If storage size is erroneously variable, just continue.
- Error message was already made. */
-
- if (! TREE_LITERAL (DECL_SIZE (decl)))
- return;
-
- app_disable ();
-
- name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
-
- /* Handle uninitialized definitions. */
-
- if (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node)
- {
- int size = (TREE_INT_CST_LOW (DECL_SIZE (decl))
- * DECL_SIZE_UNIT (decl)
- / BITS_PER_UNIT);
- int rounded = size;
- /* Don't allocate zero bytes of common,
- since that means "undefined external" in the linker. */
- if (size == 0) rounded = 1;
- /* Round size up to multiple of BIGGEST_ALIGNMENT bits
- so that each uninitialized object starts on such a boundary. */
- rounded = ((rounded + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
- / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
- * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
- if (flag_shared_data)
- data_section ();
- if (TREE_PUBLIC (decl))
- ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
- else
- ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
- return;
- }
-
- /* Handle initialized definitions. */
-
- /* First make the assembler name(s) global if appropriate. */
- if (TREE_PUBLIC (decl) && DECL_NAME (decl))
- {
- if (!first_global_object_name)
- first_global_object_name = name + (name[0] == '*');
- ASM_GLOBALIZE_LABEL (asm_out_file, name);
- }
- #if 0
- for (d = equivalents; d; d = TREE_CHAIN (d))
- {
- tree e = TREE_VALUE (d);
- if (TREE_PUBLIC (e) && DECL_NAME (e))
- ASM_GLOBALIZE_LABEL (asm_out_file,
- XSTR (XEXP (DECL_RTL (e), 0), 0));
- }
- #endif
-
- /* Output any data that we will need to use the address of. */
- if (DECL_INITIAL (decl))
- output_addressed_constants (DECL_INITIAL (decl));
-
- /* Switch to the proper section for this data. */
- #ifdef SELECT_SECTION
- SELECT_SECTION (decl);
- #else
- if (TREE_READONLY (decl) && ! TREE_VOLATILE (decl))
- text_section ();
- else
- data_section ();
- #endif
-
- /* Output the alignment of this data. */
- #ifdef DATA_ALIGNMENT
- /* On some machines, it is good to increase alignment sometimes. */
- align = DATA_ALIGNMENT (decl, DECL_ALIGN (decl));
- #else /* no DATA_ALIGNMENT */
- align = DECL_ALIGN (decl);
- #endif /* DATA_ALIGNMENT */
-
- for (i = 0; align >= BITS_PER_UNIT << (i + 1); i++);
- if (i > 0)
- ASM_OUTPUT_ALIGN (asm_out_file, i);
-
- /* Output the name(s) of this data. */
- ASM_OUTPUT_LABEL (asm_out_file, name);
- #if 0
- for (d = equivalents; d; d = TREE_CHAIN (d))
- {
- tree e = TREE_VALUE (d);
- ASM_OUTPUT_LABEL (asm_out_file, XSTR (XEXP (DECL_RTL (e), 0), 0));
- }
- #endif
-
- if (DECL_INITIAL (decl))
- /* Output the actual data. */
- output_constant (DECL_INITIAL (decl), int_size_in_bytes (TREE_TYPE (decl)));
- else
- /* Leave space for it. */
- ASM_OUTPUT_SKIP (asm_out_file, int_size_in_bytes (TREE_TYPE (decl)));
- }
-
- /* Output something to declare an external symbol to the assembler.
- (Most assemblers don't need this, so we normally output nothing.) */
-
- void
- assemble_external (decl)
- tree decl;
- {
- rtx rtl = DECL_RTL (decl);
-
- if (GET_CODE (rtl) == MEM && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF)
- {
- #ifdef ASM_OUTPUT_EXTERNAL
- /* Some systems do require some output. */
- ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
- #endif
- }
- }
-
- /* Output to FILE a reference to the assembler name of a C-level name NAME.
- If NAME starts with a *, the rest of NAME is output verbatim.
- Otherwise NAME is transformed in an implementation-defined way
- (usually by the addition of an underscore).
- Many macros in the tm file are defined to call this function. */
-
- void
- assemble_name (file, name)
- FILE *file;
- char *name;
- {
- if (name[0] == '*')
- fputs (&name[1], file);
- else
- ASM_OUTPUT_LABELREF (file, name);
- }
-
- /* Allocate SIZE bytes writable static space with a gensym name
- and return an RTX to refer to its address. */
-
- rtx
- assemble_static_space (size)
- int size;
- {
- char name[12];
- char *namestring;
- rtx x;
- /* Round size up to multiple of BIGGEST_ALIGNMENT bits
- so that each uninitialized object starts on such a boundary. */
- int rounded = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
- / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
- * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
-
- if (flag_shared_data)
- data_section ();
- ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
- ++const_labelno;
-
- namestring = (char *) obstack_alloc (saveable_obstack,
- strlen (name) + 2);
- strcpy (namestring, name);
-
- x = gen_rtx (SYMBOL_REF, Pmode, namestring);
- ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
- return x;
- }
- #if 0
- /* Assemble the static constant template for function entry trampolines.
- This is done at most once per compilation.
- Returns an RTX for the address of the template. */
-
- rtx
- assemble_trampoline_template ()
- {
- char label[256];
- char *name;
- int align;
-
- /* Write the assembler code to define one. */
- align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
- if (align > 0)
- ASM_OUTPUT_ALIGN (asm_out_file, align);
-
- ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LTRAMP", 0);
- TRAMPOLINE_TEMPLATE (asm_out_file);
-
- /* Record the rtl to refer to it. */
- ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
- name
- = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label));
- return gen_rtx (SYMBOL_REF, Pmode, name);
- }
- #endif
-
- /* Here we combine duplicate floating constants to make
- CONST_DOUBLE rtx's, and force those out to memory when necessary. */
-
- /* Chain of all CONST_DOUBLE rtx's constructed for the current function.
- They are chained through the CONST_DOUBLE_CHAIN.
- A CONST_DOUBLE rtx has CONST_DOUBLE_MEM != cc0_rtx iff it is on this chain.
- In that case, CONST_DOUBLE_MEM is either a MEM,
- or const0_rtx if no MEM has been made for this CONST_DOUBLE yet. */
-
- static rtx real_constant_chain;
-
- /* Return a CONST_DOUBLE for a value specified as a pair of ints.
- For an integer, I0 is the low-order word and I1 is the high-order word.
- For a real number, I0 is the word with the low address
- and I1 is the word with the high address. */
-
- rtx
- immed_double_const (i0, i1, mode)
- int i0, i1;
- enum machine_mode mode;
- {
- register rtx r;
-
- if (mode == DImode && i0 == 0 && i1 == 0)
- return const0_rtx;
-
- /* Search the chain for an existing CONST_DOUBLE with the right value.
- If one is found, return it. */
-
- for (r = real_constant_chain; r; r = CONST_DOUBLE_CHAIN (r))
- if (CONST_DOUBLE_LOW (r) == i0 && CONST_DOUBLE_HIGH (r) == i1
- && GET_MODE (r) == mode)
- return r;
-
- /* No; make a new one and add it to the chain. */
-
- r = gen_rtx (CONST_DOUBLE, mode, 0, i0, i1);
-
- CONST_DOUBLE_CHAIN (r) = real_constant_chain;
- real_constant_chain = r;
-
- /* Store const0_rtx in mem-slot since this CONST_DOUBLE is on the chain.
- Actual use of mem-slot is only through force_const_double_mem. */
-
- CONST_DOUBLE_MEM (r) = const0_rtx;
-
- return r;
- }
-
- /* Return a CONST_DOUBLE for a specified `double' value
- and machine mode. */
-
- rtx
- immed_real_const_1 (d, mode)
- REAL_VALUE_TYPE d;
- enum machine_mode mode;
- {
- union real_extract u;
- register rtx r;
- REAL_VALUE_TYPE negated;
-
- /* Get the desired `double' value as a sequence of ints
- since that is how they are stored in a CONST_DOUBLE. */
-
- u.d = d;
-
- #if 0
- /* Detect special cases. */
-
- if (REAL_VALUES_EQUAL (dconst0, d))
- return (mode == DFmode ? dconst0_rtx : fconst0_rtx);
- else if (REAL_VALUES_EQUAL (dconst1, d))
- return (mode == DFmode ? dconst1_rtx : fconst1_rtx);
-
- if (sizeof u == 2 * sizeof (int))
- return immed_double_const (u.i[0], u.i[1], mode);
- #else
- /* Detect zero. */
-
- negated = REAL_VALUE_NEGATE (d);
- if (REAL_VALUES_EQUAL (negated, d))
- return (mode == DFmode ? dconst0_rtx : fconst0_rtx);
-
- if (sizeof u == 2 * sizeof (int))
- return immed_double_const (u.i[0], u.i[1], mode);
- #endif
-
- /* The rest of this function handles the case where
- a float value requires more than 2 ints of space.
- It will be deleted as dead code on machines that don't need it. */
-
- /* Search the chain for an existing CONST_DOUBLE with the right value.
- If one is found, return it. */
-
- for (r = real_constant_chain; r; r = CONST_DOUBLE_CHAIN (r))
- if (! bcmp (&CONST_DOUBLE_LOW (r), &u, sizeof u)
- && GET_MODE (r) == mode)
- return r;
-
- /* No; make a new one and add it to the chain. */
-
- r = rtx_alloc (CONST_DOUBLE);
- PUT_MODE (r, mode);
- bcopy (&u, &CONST_DOUBLE_LOW (r), sizeof u);
-
- CONST_DOUBLE_CHAIN (r) = real_constant_chain;
- real_constant_chain = r;
-
- /* Store const0_rtx in slot 2 since this CONST_DOUBLE is on the chain.
- Actual use of slot 2 is only through force_const_double_mem. */
-
- CONST_DOUBLE_MEM (r) = const0_rtx;
-
- return r;
- }
-
- /* Return a CONST_DOUBLE rtx for a value specified by EXP,
- which must be a REAL_CST tree node. */
-
- rtx
- immed_real_const (exp)
- tree exp;
- {
- return immed_real_const_1 (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)));
- }
-
- /* Given a CONST_DOUBLE, cause a constant in memory to be created
- (unless we already have one for the same value)
- and return a MEM rtx to refer to it.
- Put the CONST_DOUBLE on real_constant_chain if it isn't already there. */
-
- rtx
- force_const_double_mem (r)
- rtx r;
- {
- if (GET_CODE (CONST_DOUBLE_MEM (r)) != MEM)
- force_const_mem (GET_MODE (r), r);
-
- /* CONST_DOUBLE_MEM (r) is now a MEM with a constant address.
- If that is legitimate, return it.
- Othewise it will need reloading, so return a copy of it. */
- if (memory_address_p (GET_MODE (r), XEXP (CONST_DOUBLE_MEM (r), 0)))
- return CONST_DOUBLE_MEM (r);
- return gen_rtx (MEM, GET_MODE (r), XEXP (CONST_DOUBLE_MEM (r), 0));
- }
-
- /* At the end of a function, forget the memory-constants
- previously made for CONST_DOUBLEs. Mark them as not on real_constant_chain.
- Also clear out real_constant_chain and clear out all the chain-pointers. */
-
- void
- clear_const_double_mem ()
- {
- register rtx r, next;
-
- for (r = real_constant_chain; r; r = next)
- {
- next = CONST_DOUBLE_CHAIN (r);
- CONST_DOUBLE_CHAIN (r) = 0;
- CONST_DOUBLE_MEM (r) = cc0_rtx;
- }
- real_constant_chain = 0;
- }
-
- /* Given an expression EXP with a constant value,
- reduce it to the sum of an assembler symbol and an integer.
- Store them both in the structure *VALUE.
- Abort if EXP does not reduce. */
-
- struct addr_const
- {
- rtx base;
- int offset;
- };
-
- static void
- decode_addr_const (exp, value)
- tree exp;
- struct addr_const *value;
- {
- register tree target = TREE_OPERAND (exp, 0);
- register int offset = 0;
- register rtx x;
-
- while (1)
- {
- if (TREE_CODE (target) == COMPONENT_REF)
- {
- offset += DECL_OFFSET (TREE_OPERAND (target, 1)) / BITS_PER_UNIT;
- target = TREE_OPERAND (target, 0);
- }
- else if (TREE_CODE (target) == ARRAY_REF)
- {
- if (TREE_CODE (TREE_OPERAND (target, 1)) != INTEGER_CST
- || TREE_CODE (TYPE_SIZE (TREE_TYPE (target))) != INTEGER_CST)
- abort ();
- offset += ((TYPE_SIZE_UNIT (TREE_TYPE (target))
- * TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (target)))
- * TREE_INT_CST_LOW (TREE_OPERAND (target, 1)))
- / BITS_PER_UNIT);
- target = TREE_OPERAND (target, 0);
- }
- else break;
- }
-
- if (TREE_CODE (target) == VAR_DECL
- || TREE_CODE (target) == FUNCTION_DECL)
- x = DECL_RTL (target);
- else if (TREE_LITERAL (target))
- x = TREE_CST_RTL (target);
- else
- abort ();
-
- if (GET_CODE (x) != MEM)
- abort ();
- x = XEXP (x, 0);
-
- value->base = x;
- value->offset = offset;
- }
-
- /* Uniquize all constants that appear in memory.
- Each constant in memory thus far output is recorded
- in `const_hash_table' with a `struct constant_descriptor'
- that contains a polish representation of the value of
- the constant.
-
- We cannot store the trees in the hash table
- because the trees may be temporary. */
-
- struct constant_descriptor
- {
- struct constant_descriptor *next;
- char *label;
- char contents[1];
- };
-
- #define HASHBITS 30
- #define MAX_HASH_TABLE 1009
- static struct constant_descriptor *const_hash_table[MAX_HASH_TABLE];
-
- /* Compute a hash code for a constant expression. */
-
- int
- const_hash (exp)
- tree exp;
- {
- register char *p;
- register int len, hi, i;
- register enum tree_code code = TREE_CODE (exp);
-
- if (code == INTEGER_CST)
- {
- p = (char *) &TREE_INT_CST_LOW (exp);
- len = 2 * sizeof TREE_INT_CST_LOW (exp);
- }
- else if (code == REAL_CST)
- {
- p = (char *) &TREE_REAL_CST (exp);
- len = sizeof TREE_REAL_CST (exp);
- }
- else if (code == STRING_CST)
- p = TREE_STRING_POINTER (exp), len = TREE_STRING_LENGTH (exp);
- else if (code == COMPLEX_CST)
- return const_hash (TREE_REALPART (exp)) * 5
- + const_hash (TREE_IMAGPART (exp));
- else if (code == CONSTRUCTOR)
- {
- register tree link;
-
- /* For record type, include the type in the hashing.
- We do not do so for array types
- because (1) the sizes of the elements are sufficient
- and (2) distinct array types can have the same constructor. */
- if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE)
- hi = ((int) TREE_TYPE (exp) & ((1 << HASHBITS) - 1)) % MAX_HASH_TABLE;
- else
- hi = 5;
-
- for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
- hi = (hi * 603 + const_hash (TREE_VALUE (link))) % MAX_HASH_TABLE;
-
- return hi;
- }
- else if (code == ADDR_EXPR)
- {
- struct addr_const value;
- decode_addr_const (exp, &value);
- p = (char *) &value;
- len = sizeof value;
- }
- else if (code == PLUS_EXPR || code == MINUS_EXPR)
- return const_hash (TREE_OPERAND (exp, 0)) * 9
- + const_hash (TREE_OPERAND (exp, 1));
- else if (code == NOP_EXPR || code == CONVERT_EXPR)
- return const_hash (TREE_OPERAND (exp, 0)) * 7 + 2;
-
- /* Compute hashing function */
- hi = len;
- for (i = 0; i < len; i++)
- hi = ((hi * 613) + (unsigned)(p[i]));
-
- hi &= (1 << HASHBITS) - 1;
- hi %= MAX_HASH_TABLE;
- return hi;
- }
-
- /* Compare a constant expression EXP with a constant-descriptor DESC.
- Return 1 if DESC describes a constant with the same value as EXP. */
-
- static int
- compare_constant (exp, desc)
- tree exp;
- struct constant_descriptor *desc;
- {
- return 0 != compare_constant_1 (exp, desc->contents);
- }
-
- /* Compare constant expression EXP with a substring P of a constant descriptor.
- If they match, return a pointer to the end of the substring matched.
- If they do not match, return 0.
-
- Since descriptors are written in polish prefix notation,
- this function can be used recursively to test one operand of EXP
- against a subdescriptor, and if it succeeds it returns the
- address of the subdescriptor for the next operand. */
-
- static char *
- compare_constant_1 (exp, p)
- tree exp;
- char *p;
- {
- register char *strp;
- register int len;
- register enum tree_code code = TREE_CODE (exp);
-
- if (code != (enum tree_code) *p++)
- return 0;
-
- if (code == INTEGER_CST)
- {
- /* Integer constants are the same only if the same width of type. */
- if (*p++ != TYPE_PRECISION (TREE_TYPE (exp)))
- return 0;
- strp = (char *) &TREE_INT_CST_LOW (exp);
- len = 2 * sizeof TREE_INT_CST_LOW (exp);
- }
- else if (code == REAL_CST)
- {
- /* Real constants are the same only if the same width of type. */
- if (*p++ != TYPE_PRECISION (TREE_TYPE (exp)))
- return 0;
- strp = (char *) &TREE_REAL_CST (exp);
- len = sizeof TREE_REAL_CST (exp);
- }
- else if (code == STRING_CST)
- {
- if (flag_writable_strings)
- return 0;
- strp = TREE_STRING_POINTER (exp);
- len = TREE_STRING_LENGTH (exp);
- if (bcmp (&TREE_STRING_LENGTH (exp), p,
- sizeof TREE_STRING_LENGTH (exp)))
- return 0;
- p += sizeof TREE_STRING_LENGTH (exp);
- }
- else if (code == COMPLEX_CST)
- {
- p = compare_constant_1 (TREE_REALPART (exp), p);
- if (p == 0) return 0;
- p = compare_constant_1 (TREE_IMAGPART (exp), p);
- return p;
- }
- else if (code == CONSTRUCTOR)
- {
- register tree link;
- int length = list_length (CONSTRUCTOR_ELTS (exp));
- tree type;
-
- if (bcmp (&length, p, sizeof length))
- return 0;
- p += sizeof length;
-
- /* For record constructors, insist that the types match.
- For arrays, just verify both constructors are for arrays. */
- if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE)
- type = TREE_TYPE (exp);
- else
- type = 0;
- if (bcmp (&type, p, sizeof type))
- return 0;
- p += sizeof type;
-
- for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
- if ((p = compare_constant_1 (TREE_VALUE (link), p)) == 0)
- return 0;
- return p;
- }
- else if (code == ADDR_EXPR)
- {
- struct addr_const value;
- decode_addr_const (exp, &value);
- strp = (char *) &value;
- len = sizeof value;
- /* Compare SYMBOL_REF address and offset. */
- while (--len >= 0)
- if (*p++ != *strp++)
- return 0;
- /* Compare symbol name. */
- strp = XSTR (value.base, 0);
- len = strlen (strp) + 1;
- }
- else if (code == PLUS_EXPR || code == MINUS_EXPR)
- {
- p = compare_constant_1 (TREE_OPERAND (exp, 0), p);
- if (p == 0) return 0;
- p = compare_constant_1 (TREE_OPERAND (exp, 1), p);
- return p;
- }
- else if (code == NOP_EXPR || code == CONVERT_EXPR)
- {
- p = compare_constant_1 (TREE_OPERAND (exp, 0), p);
- return p;
- }
-
- /* Compare constant contents. */
- while (--len >= 0)
- if (*p++ != *strp++)
- return 0;
-
- return p;
- }
-
- /* Construct a constant descriptor for the expression EXP.
- It is up to the caller to enter the descriptor in the hash table. */
-
- static struct constant_descriptor *
- record_constant (exp)
- tree exp;
- {
- struct constant_descriptor *ptr = 0;
- int buf;
-
- obstack_grow (&permanent_obstack, &ptr, sizeof ptr);
- obstack_grow (&permanent_obstack, &buf, sizeof buf);
- record_constant_1 (exp);
- return (struct constant_descriptor *) obstack_finish (&permanent_obstack);
- }
-
- /* Add a description of constant expression EXP
- to the object growing in `permanent_obstack'.
- No need to return its address; the caller will get that
- from the obstack when the object is complete. */
-
- static void
- record_constant_1 (exp)
- tree exp;
- {
- register char *strp;
- register int len;
- register enum tree_code code = TREE_CODE (exp);
-
- obstack_1grow (&permanent_obstack, (unsigned int) code);
-
- if (code == INTEGER_CST)
- {
- obstack_1grow (&permanent_obstack, TYPE_PRECISION (TREE_TYPE (exp)));
- strp = (char *) &TREE_INT_CST_LOW (exp);
- len = 2 * sizeof TREE_INT_CST_LOW (exp);
- }
- else if (code == REAL_CST)
- {
- obstack_1grow (&permanent_obstack, TYPE_PRECISION (TREE_TYPE (exp)));
- strp = (char *) &TREE_REAL_CST (exp);
- len = sizeof TREE_REAL_CST (exp);
- }
- else if (code == STRING_CST)
- {
- if (flag_writable_strings)
- return;
- strp = TREE_STRING_POINTER (exp);
- len = TREE_STRING_LENGTH (exp);
- obstack_grow (&permanent_obstack, (char *) &TREE_STRING_LENGTH (exp),
- sizeof TREE_STRING_LENGTH (exp));
- }
- else if (code == COMPLEX_CST)
- {
- record_constant_1 (TREE_REALPART (exp));
- record_constant_1 (TREE_IMAGPART (exp));
- return;
- }
- else if (code == CONSTRUCTOR)
- {
- register tree link;
- int length = list_length (CONSTRUCTOR_ELTS (exp));
- tree type;
-
- obstack_grow (&permanent_obstack, (char *) &length, sizeof length);
-
- /* For record constructors, insist that the types match.
- For arrays, just verify both constructors are for arrays. */
- if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE)
- type = TREE_TYPE (exp);
- else
- type = 0;
- obstack_grow (&permanent_obstack, (char *) &type, sizeof type);
-
- for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
- record_constant_1 (TREE_VALUE (link));
- return;
- }
- else if (code == ADDR_EXPR)
- {
- struct addr_const value;
- decode_addr_const (exp, &value);
- /* Record the SYMBOL_REF address and the offset. */
- obstack_grow (&permanent_obstack, (char *) &value, sizeof value);
- /* Record the symbol name. */
- obstack_grow (&permanent_obstack, XSTR (value.base, 0),
- strlen (XSTR (value.base, 0)) + 1);
- return;
- }
- else if (code == PLUS_EXPR || code == MINUS_EXPR)
- {
- record_constant_1 (TREE_OPERAND (exp, 0));
- record_constant_1 (TREE_OPERAND (exp, 1));
- return;
- }
- else if (code == NOP_EXPR || code == CONVERT_EXPR)
- {
- record_constant_1 (TREE_OPERAND (exp, 0));
- return;
- }
-
- /* Record constant contents. */
- obstack_grow (&permanent_obstack, strp, len);
- }
-
- /* Return the constant-label-string for constant value EXP.
- If no constant equal to EXP has yet been output,
- define a new label and output assembler code for it.
- The const_hash_table records which constants already have label strings. */
-
- static char *
- get_or_assign_label (exp)
- tree exp;
- {
- register int hash, i, align;
- register struct constant_descriptor *desc;
- char label[256];
-
- /* Make sure any other constants whose addresses appear in EXP
- are assigned label numbers. */
-
- output_addressed_constants (exp);
-
- /* Compute hash code of EXP. Search the descriptors for that hash code
- to see if any of them describes EXP. If yes, the descriptor records
- the label number already assigned. */
-
- hash = const_hash (exp) % MAX_HASH_TABLE;
-
- for (desc = const_hash_table[hash]; desc; desc = desc->next)
- if (compare_constant (exp, desc))
- return desc->label;
-
- /* No constant equal to EXP is known to have been output.
- Make a constant descriptor to enter EXP in the hash table.
- Assign the label number and record it in the descriptor for
- future calls to this function to find. */
-
- desc = record_constant (exp);
- desc->next = const_hash_table[hash];
- const_hash_table[hash] = desc;
-
- /* Now output assembler code to define that label
- and follow it with the data of EXP. */
-
- /* First switch to text section, except for writable strings. */
- #ifdef SELECT_SECTION
- SELECT_SECTION (exp);
- #else
- if ((TREE_CODE (exp) == STRING_CST) && flag_writable_strings)
- data_section ();
- else
- text_section ();
- #endif
-
- /* Align the location counter as required by EXP's data type. */
- #ifdef DATA_ALIGNMENT
- align = DATA_ALIGNMENT (exp, TYPE_ALIGN (TREE_TYPE (exp)));
- #else
- align = TYPE_ALIGN (TREE_TYPE (exp));
- #endif
-
- for (i = 0; align >= BITS_PER_UNIT << (i + 1); i++);
- if (i > 0)
- ASM_OUTPUT_ALIGN (asm_out_file, i);
-
- /* Output the label itself. */
- ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", const_labelno);
-
- /* Output the value of EXP. */
- output_constant (exp,
- (TREE_CODE (exp) == STRING_CST
- ? TREE_STRING_LENGTH (exp)
- : int_size_in_bytes (TREE_TYPE (exp))));
-
- /* Create a string containing the label name, in LABEL. */
- ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
-
- ++const_labelno;
-
- desc->label
- = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label));
-
- return desc->label;
- }
-
- /* Return an rtx representing a reference to constant data in memory
- for the constant expression EXP.
- If assembler code for such a constant has already been output,
- return an rtx to refer to it.
- Otherwise, output such a constant in memory and generate
- an rtx for it. The TREE_CST_RTL of EXP is set up to point to that rtx. */
-
- rtx
- output_constant_def (exp)
- tree exp;
- {
- register rtx def;
- int temp_p = allocation_temporary_p ();
-
- if (TREE_CODE (exp) == INTEGER_CST)
- abort (); /* No TREE_CST_RTL slot in these. */
-
- if (TREE_CST_RTL (exp))
- return TREE_CST_RTL (exp);
-
- if (TREE_PERMANENT (exp))
- end_temporary_allocation ();
-
- def = gen_rtx (SYMBOL_REF, Pmode, get_or_assign_label (exp));
-
- TREE_CST_RTL (exp)
- = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)), def);
- RTX_UNCHANGING_P (TREE_CST_RTL (exp)) = 1;
-
- if (temp_p && TREE_PERMANENT (exp))
- resume_temporary_allocation ();
-
- return TREE_CST_RTL (exp);
- }
-
- /* Similar hash facility for making memory-constants
- from constant rtl-expressions. It is used on RISC machines
- where immediate integer arguments and constant addresses are restricted
- so that such constants must be stored in memory.
-
- This pool of constants is reinitialized for each function
- so each function gets its own constants-pool that comes right before it.
-
- All structures allocated here are discarded when functions are saved for
- inlining, so they do not need to be allocated permanently. */
-
- #define MAX_RTX_HASH_TABLE 61
- static struct constant_descriptor *const_rtx_hash_table[MAX_RTX_HASH_TABLE];
-
- /* Structure to represent sufficient information about a constant so that
- it can be output when the constant pool is output, so that function
- integration can be done, and to simplify handling on machines that reference
- constant pool as base+displacement. */
-
- struct pool_constant
- {
- struct constant_descriptor *desc;
- struct pool_constant *next;
- enum machine_mode mode;
- rtx constant;
- int labelno;
- int align;
- int offset;
- };
-
- /* Pointers to first and last constant in pool. */
-
- static struct pool_constant *first_pool, *last_pool;
-
- /* Current offset in constant pool (does not include any machine-specific
- header. */
-
- static int pool_offset;
-
- /* Structure used to maintain hash table mapping symbols used to their
- corresponding constants. */
-
- struct pool_sym
- {
- char *label;
- struct pool_constant *pool;
- struct pool_sym *next;
- };
-
- static struct pool_sym *const_rtx_sym_hash_table[MAX_RTX_HASH_TABLE];
-
- /* Hash code for a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true.
- The argument is XSTR (... , 0) */
-
- #define SYMHASH(LABEL) \
- ((((int) (LABEL)) & ((1 << HASHBITS) - 1)) % MAX_RTX_HASH_TABLE)
-
- /* Initialize constant pool hashing for next function. */
-
- void
- init_const_rtx_hash_table ()
- {
- bzero (const_rtx_hash_table, sizeof const_rtx_hash_table);
- bzero (const_rtx_sym_hash_table, sizeof const_rtx_sym_hash_table);
-
- first_pool = last_pool = 0;
- pool_offset = 0;
- }
-
- struct rtx_const
- {
- enum kind { RTX_DOUBLE, RTX_INT } kind : 16;
- enum machine_mode mode : 16;
- union {
- union real_extract du;
- struct addr_const addr;
- } un;
- };
-
- /* Express an rtx for a constant integer (perhaps symbolic)
- as the sum of a symbol or label plus an explicit integer.
- They are stored into VALUE. */
-
- static void
- decode_rtx_const (mode, x, value)
- enum machine_mode mode;
- rtx x;
- struct rtx_const *value;
- {
- /* Clear the whole structure, including any gaps. */
-
- {
- int *p = (int *) value;
- int *end = (int *) (value + 1);
- while (p < end)
- *p++ = 0;
- }
-
- value->kind = RTX_INT; /* Most usual kind. */
- value->mode = mode;
-
- switch (GET_CODE (x))
- {
- case CONST_DOUBLE:
- value->kind = RTX_DOUBLE;
- value->mode = GET_MODE (x);
- bcopy (&CONST_DOUBLE_LOW (x), &value->un.du, sizeof value->un.du);
- break;
-
- case CONST_INT:
- value->un.addr.offset = INTVAL (x);
- break;
-
- case SYMBOL_REF:
- value->un.addr.base = x;
- break;
-
- case LABEL_REF:
- value->un.addr.base = x;
- break;
-
- case CONST:
- x = XEXP (x, 0);
- if (GET_CODE (x) == PLUS)
- {
- value->un.addr.base = XEXP (XEXP (x, 0), 0);
- if (GET_CODE (XEXP (x, 1)) != CONST_INT)
- abort ();
- value->un.addr.offset = INTVAL (XEXP (x, 1));
- }
- else if (GET_CODE (x) == MINUS)
- {
- value->un.addr.base = XEXP (x, 0);
- if (GET_CODE (XEXP (x, 1)) != CONST_INT)
- abort ();
- value->un.addr.offset = - INTVAL (XEXP (x, 1));
- }
- else
- abort ();
- break;
-
- default:
- abort ();
- }
-
- if (value->kind == RTX_INT && value->un.addr.base != 0)
- switch (GET_CODE (value->un.addr.base))
- {
- case SYMBOL_REF:
- case LABEL_REF:
- /* Use the string's address, not the SYMBOL_REF's address,
- for the sake of addresses of library routines.
- For a LABEL_REF, compare labels. */
- value->un.addr.base = XEXP (value->un.addr.base, 0);
- }
- }
-
- /* Compute a hash code for a constant RTL expression. */
-
- int
- const_hash_rtx (mode, x)
- enum machine_mode mode;
- rtx x;
- {
- register int hi, i;
-
- struct rtx_const value;
- decode_rtx_const (mode, x, &value);
-
- /* Compute hashing function */
- hi = 0;
- for (i = 0; i < sizeof value / sizeof (int); i++)
- hi += ((int *) &value)[i];
-
- hi &= (1 << HASHBITS) - 1;
- hi %= MAX_RTX_HASH_TABLE;
- return hi;
- }
-
- /* Compare a constant rtl object X with a constant-descriptor DESC.
- Return 1 if DESC describes a constant with the same value as X. */
-
- static int
- compare_constant_rtx (mode, x, desc)
- enum machine_mode mode;
- rtx x;
- struct constant_descriptor *desc;
- {
- register int *p = (int *) desc->contents;
- register int *strp;
- register int len;
- struct rtx_const value;
-
- decode_rtx_const (mode, x, &value);
- strp = (int *) &value;
- len = sizeof value / sizeof (int);
-
- /* Compare constant contents. */
- while (--len >= 0)
- if (*p++ != *strp++)
- return 0;
-
- return 1;
- }
-
- /* Construct a constant descriptor for the rtl-expression X.
- It is up to the caller to enter the descriptor in the hash table. */
-
- static struct constant_descriptor *
- record_constant_rtx (mode, x)
- enum machine_mode mode;
- rtx x;
- {
- struct constant_descriptor *ptr;
- char *label;
- struct rtx_const value;
-
- decode_rtx_const (mode, x, &value);
-
- obstack_grow (current_obstack, &ptr, sizeof ptr);
- obstack_grow (current_obstack, &label, sizeof label);
-
- /* Record constant contents. */
- obstack_grow (current_obstack, &value, sizeof value);
-
- return (struct constant_descriptor *) obstack_finish (current_obstack);
- }
-
- /* Given a constant rtx X, make (or find) a memory constant for its value
- and return a MEM rtx to refer to it in memory. */
-
- rtx
- force_const_mem (mode, x)
- enum machine_mode mode;
- rtx x;
- {
- register int hash;
- register struct constant_descriptor *desc;
- char label[256];
- char *found = 0;
- rtx def;
-
- if (GET_CODE (x) == CONST_DOUBLE
- && GET_CODE (CONST_DOUBLE_MEM (x)) == MEM)
- return CONST_DOUBLE_MEM (x);
-
- /* Compute hash code of X. Search the descriptors for that hash code
- to see if any of them describes X. If yes, the descriptor records
- the label number already assigned. */
-
- hash = const_hash_rtx (mode, x);
-
- for (desc = const_rtx_hash_table[hash]; desc; desc = desc->next)
- if (compare_constant_rtx (mode, x, desc))
- {
- found = desc->label;
- break;
- }
-
- if (found == 0)
- {
- register struct pool_constant *pool;
- register struct pool_sym *sym;
- int align;
-
- /* No constant equal to X is known to have been output.
- Make a constant descriptor to enter X in the hash table.
- Assign the label number and record it in the descriptor for
- future calls to this function to find. */
-
- desc = record_constant_rtx (mode, x);
- desc->next = const_rtx_hash_table[hash];
- const_rtx_hash_table[hash] = desc;
-
- /* Align the location counter as required by EXP's data type. */
- align = (mode == VOIDmode) ? UNITS_PER_WORD : GET_MODE_SIZE (mode);
- if (align > BIGGEST_ALIGNMENT / BITS_PER_UNIT)
- align = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
-
- pool_offset += align - 1;
- pool_offset &= ~ (align - 1);
-
- /* Allocate a pool constant descriptor, fill it in, and chain it in. */
-
- pool = (struct pool_constant *) oballoc (sizeof (struct pool_constant));
- pool->desc = desc;
- pool->constant = x;
- pool->mode = mode;
- pool->labelno = const_labelno;
- pool->align = align;
- pool->offset = pool_offset;
- pool->next = 0;
-
- if (last_pool == 0)
- first_pool = pool;
- else
- last_pool->next = pool;
-
- last_pool = pool;
- pool_offset += GET_MODE_SIZE (mode);
-
- /* Create a string containing the label name, in LABEL. */
- ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
-
- ++const_labelno;
-
- desc->label = found
- = (char *) obstack_copy0 (saveable_obstack, label, strlen (label));
-
- /* Add label to symbol hash table. */
- hash = SYMHASH (found);
- sym = (struct pool_sym *) oballoc (sizeof (struct pool_sym));
- sym->label = found;
- sym->pool = pool;
- sym->next = const_rtx_sym_hash_table[hash];
- const_rtx_sym_hash_table[hash] = sym;
- }
-
- /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
-
- def = gen_rtx (MEM, mode, gen_rtx (SYMBOL_REF, Pmode, found));
-
- RTX_UNCHANGING_P (def) = 1;
- /* Mark the symbol_ref as belonging to this constants pool. */
- CONSTANT_POOL_ADDRESS_P (XEXP (def, 0)) = 1;
-
- if (GET_CODE (x) == CONST_DOUBLE)
- {
- if (CONST_DOUBLE_MEM (x) == cc0_rtx)
- {
- CONST_DOUBLE_CHAIN (x) = real_constant_chain;
- real_constant_chain = x;
- }
- CONST_DOUBLE_MEM (x) = def;
- }
-
- return def;
- }
-
- /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
- the corresponding pool_constant structure. */
-
- static struct pool_constant *
- find_pool_constant (addr)
- rtx addr;
- {
- struct pool_sym *sym;
- char *label = XSTR (addr, 0);
-
- for (sym = const_rtx_sym_hash_table[SYMHASH (label)]; sym; sym = sym->next)
- if (sym->label == label)
- return sym->pool;
-
- abort ();
- }
-
- /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
-
- rtx
- get_pool_constant (addr)
- rtx addr;
- {
- return (find_pool_constant (addr))->constant;
- }
-
- /* Similar, return the mode. */
-
- enum machine_mode
- get_pool_mode (addr)
- rtx addr;
- {
- return (find_pool_constant (addr))->mode;
- }
-
- /* Similar, return the offset in the constant pool. */
-
- int
- get_pool_offset (addr)
- rtx addr;
- {
- return (find_pool_constant (addr))->offset;
- }
-
- /* Write all the constants in the constant pool. */
-
- void
- output_constant_pool (fnname, fndecl)
- char *fnname;
- tree fndecl;
- {
- struct pool_constant *pool;
- rtx x;
-
- #ifdef ASM_OUTPUT_POOL_PROLOGUE
- ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool_offset);
- #endif
-
- for (pool = first_pool; pool; pool = pool->next)
- {
- x = pool->constant;
-
- /* First switch to correct section. */
- #ifdef SELECT_RTX_SECTION
- SELECT_RTX_SECTION (pool->mode, x);
- #else
- text_section ();
- #endif
-
- if (pool->align > 1)
- ASM_OUTPUT_ALIGN (asm_out_file, exact_log2 (pool->align));
-
- /* Output the label. */
- ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", pool->labelno);
-
- /* Output the value of the constant itself. */
- if (GET_CODE (x) == CONST_DOUBLE)
- {
- union real_extract u;
-
- bcopy (&CONST_DOUBLE_LOW (x), &u, sizeof u);
- switch (pool->mode)
- {
- /* Perhaps change the following to use
- CONST_DOUBLE_LOW and CONST_DOUBLE_HIGH, rather than u.i. */
- case DImode:
- #ifdef ASM_OUTPUT_DOUBLE_INT
- ASM_OUTPUT_DOUBLE_INT (asm_out_file, x);
- #else /* no ASM_OUTPUT_DOUBLE_INT */
- #ifndef WORDS_BIG_ENDIAN
- /* Output two ints. */
- ASM_OUTPUT_INT (asm_out_file,
- gen_rtx (CONST_INT, VOIDmode, u.i[0]));
- ASM_OUTPUT_INT (asm_out_file,
- gen_rtx (CONST_INT, VOIDmode, u.i[1]));
- #else
- /* Output two ints. */
- ASM_OUTPUT_INT (asm_out_file,
- gen_rtx (CONST_INT, VOIDmode, u.i[1]));
- ASM_OUTPUT_INT (asm_out_file,
- gen_rtx (CONST_INT, VOIDmode, u.i[0]));
- #endif /* WORDS_BIG_ENDIAN */
- #endif /* no ASM_OUTPUT_DOUBLE_INT */
- break;
-
- case DFmode:
- ASM_OUTPUT_DOUBLE (asm_out_file, u.d);
- break;
-
- case SFmode:
- ASM_OUTPUT_FLOAT (asm_out_file, u.d);
- }
- }
- else
- switch (pool->mode)
- {
- case SImode:
- ASM_OUTPUT_INT (asm_out_file, x);
- break;
-
- case HImode:
- ASM_OUTPUT_SHORT (asm_out_file, x);
- break;
-
- case QImode:
- ASM_OUTPUT_CHAR (asm_out_file, x);
- break;
- }
- }
- /* Done with this pool. */
- first_pool = last_pool = 0;
- }
-
- /* Find all the constants whose addresses are referenced inside of EXP,
- and make sure assembler code with a label has been output for each one. */
-
- void
- output_addressed_constants (exp)
- tree exp;
- {
- switch (TREE_CODE (exp))
- {
- case ADDR_EXPR:
- {
- register tree constant = TREE_OPERAND (exp, 0);
-
- while (TREE_CODE (constant) == COMPONENT_REF)
- {
- constant = TREE_OPERAND (constant, 0);
- }
-
- if (TREE_LITERAL (constant))
- /* No need to do anything here
- for addresses of variables or functions. */
- output_constant_def (constant);
- }
- break;
-
- case PLUS_EXPR:
- case MINUS_EXPR:
- output_addressed_constants (TREE_OPERAND (exp, 0));
- output_addressed_constants (TREE_OPERAND (exp, 1));
- break;
-
- case NOP_EXPR:
- case CONVERT_EXPR:
- output_addressed_constants (TREE_OPERAND (exp, 0));
- break;
-
- case CONSTRUCTOR:
- {
- register tree link;
- for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
- output_addressed_constants (TREE_VALUE (link));
- }
- break;
-
- case ERROR_MARK:
- break;
-
- default:
- if (! TREE_LITERAL (exp))
- abort ();
- }
- }
-
- /* Output assembler code for constant EXP to FILE, with no label.
- This includes the pseudo-op such as ".int" or ".byte", and a newline.
- Assumes output_addressed_constants has been done on EXP already.
-
- Generate exactly SIZE bytes of assembler data, padding at the end
- with zeros if necessary. SIZE must always be specified.
-
- SIZE is important for structure constructors,
- since trailing members may have been omitted from the constructor.
- It is also important for initialization of arrays from string constants
- since the full length of the string constant might not be wanted.
- It is also needed for initialization of unions, where the initializer's
- type is just one member, and that may not be as long as the union.
-
- There a case in which we would fail to output exactly SIZE bytes:
- for a structure constructor that wants to produce more than SIZE bytes.
- But such constructors will never be generated for any possible input. */
-
- void
- output_constant (exp, size)
- register tree exp;
- register int size;
- {
- register enum tree_code code = TREE_CODE (TREE_TYPE (exp));
- rtx x;
-
- if (size == 0)
- return;
-
- /* Eliminate the NOP_EXPR that makes a cast not be an lvalue.
- That way we get the constant (we hope) inside it. */
- if (TREE_CODE (exp) == NOP_EXPR
- && TREE_TYPE (exp) == TREE_TYPE (TREE_OPERAND (exp, 0)))
- exp = TREE_OPERAND (exp, 0);
-
- switch (code)
- {
- case INTEGER_TYPE:
- case ENUMERAL_TYPE:
- case POINTER_TYPE:
- case REFERENCE_TYPE:
- while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR)
- exp = TREE_OPERAND (exp, 0);
-
- #ifndef ASM_OUTPUT_DOUBLE_INT
- if (TYPE_MODE (TREE_TYPE (exp)) == DImode)
- {
- if (TREE_CODE (exp) == INTEGER_CST)
- {
- #ifndef WORDS_BIG_ENDIAN
- ASM_OUTPUT_INT (asm_out_file,
- gen_rtx (CONST_INT, VOIDmode,
- TREE_INT_CST_LOW (exp)));
- ASM_OUTPUT_INT (asm_out_file,
- gen_rtx (CONST_INT, VOIDmode,
- TREE_INT_CST_HIGH (exp)));
- #else
- ASM_OUTPUT_INT (asm_out_file,
- gen_rtx (CONST_INT, VOIDmode,
- TREE_INT_CST_HIGH (exp)));
- ASM_OUTPUT_INT (asm_out_file,
- gen_rtx (CONST_INT, VOIDmode,
- TREE_INT_CST_LOW (exp)));
- #endif
- size -= GET_MODE_SIZE (DImode);
- break;
- }
- else
- error ("8-byte integer constant expression too complicated");
-
- break;
- }
- #endif /* no ASM_OUTPUT_DOUBLE_INT */
-
- x = expand_expr (exp, 0, VOIDmode, EXPAND_SUM);
-
- if (size == GET_MODE_SIZE (QImode))
- {
- ASM_OUTPUT_CHAR (asm_out_file, x);
- size -= GET_MODE_SIZE (QImode);
- }
- else if (size == GET_MODE_SIZE (HImode))
- {
- ASM_OUTPUT_SHORT (asm_out_file, x);
- size -= GET_MODE_SIZE (HImode);
- }
- else if (size == GET_MODE_SIZE (SImode))
- {
- ASM_OUTPUT_INT (asm_out_file, x);
- size -= GET_MODE_SIZE (SImode);
- }
- #ifdef ASM_OUTPUT_DOUBLE_INT
- else if (size == GET_MODE_SIZE (DImode))
- {
- ASM_OUTPUT_DOUBLE_INT (asm_out_file, x);
- size -= GET_MODE_SIZE (DImode);
- }
- #endif /* ASM_OUTPUT_DOUBLE_INT */
- else
- abort ();
-
- break;
-
- case REAL_TYPE:
- if (TREE_CODE (exp) != REAL_CST)
- error ("initializer for floating value is not a floating constant");
- else
- {
- REAL_VALUE_TYPE d;
- jmp_buf output_constant_handler;
-
- d = TREE_REAL_CST (exp);
- if (setjmp (output_constant_handler))
- {
- error ("floating point trap outputting a constant");
- #ifdef REAL_IS_NOT_DOUBLE
- bzero (&d, sizeof d);
- d = REAL_VALUE_ATOF ("0");
- #else
- d = 0;
- #endif
- }
- set_float_handler (output_constant_handler);
-
- if (size < GET_MODE_SIZE (SFmode))
- break;
- else if (size < GET_MODE_SIZE (DFmode))
- {
- ASM_OUTPUT_FLOAT (asm_out_file, d);
- size -= GET_MODE_SIZE (SFmode);
- }
- else
- {
- ASM_OUTPUT_DOUBLE (asm_out_file, d);
- size -= GET_MODE_SIZE (DFmode);
- }
- set_float_handler (0);
- }
- break;
-
- case COMPLEX_TYPE:
- output_constant (TREE_REALPART (exp), size / 2);
- output_constant (TREE_IMAGPART (exp), size / 2);
- size -= (size / 2) * 2;
- break;
-
- case ARRAY_TYPE:
- if (TREE_CODE (exp) == CONSTRUCTOR)
- {
- output_constructor (exp, size);
- return;
- }
- else if (TREE_CODE (exp) == STRING_CST)
- {
- int excess = 0;
-
- if (size > TREE_STRING_LENGTH (exp))
- {
- excess = size - TREE_STRING_LENGTH (exp);
- size = TREE_STRING_LENGTH (exp);
- }
-
- assemble_string (TREE_STRING_POINTER (exp), size);
- size = excess;
- }
- else
- abort ();
- break;
-
- case RECORD_TYPE:
- case UNION_TYPE:
- if (TREE_CODE (exp) == CONSTRUCTOR)
- output_constructor (exp, size);
- else
- abort ();
- return;
- }
-
- if (size > 0)
- ASM_OUTPUT_SKIP (asm_out_file, size);
- }
-
- /* Subroutine of output_constant, used for CONSTRUCTORs
- (aggregate constants).
- Generate at least SIZE bytes, padding if necessary. */
-
- void
- output_constructor (exp, size)
- tree exp;
- int size;
- {
- register tree link, field = 0;
- /* Number of bytes output or skipped so far.
- In other words, current position within the constructor. */
- int total_bytes = 0;
- /* Non-zero means BYTE contains part of a byte, to be output. */
- int byte_buffer_in_use = 0;
- register int byte;
-
- if (HOST_BITS_PER_INT < BITS_PER_UNIT)
- abort ();
-
- if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE
- || TREE_CODE (TREE_TYPE (exp)) == UNION_TYPE)
- field = TYPE_FIELDS (TREE_TYPE (exp));
-
- /* As LINK goes through the elements of the constant,
- FIELD goes through the structure fields, if the constant is a structure.
- But the constant could also be an array. Then FIELD is zero. */
- for (link = CONSTRUCTOR_ELTS (exp);
- link;
- link = TREE_CHAIN (link),
- field = field ? TREE_CHAIN (field) : 0)
- {
- tree val = TREE_VALUE (link);
-
- /* Eliminate the NOP_EXPR that makes a cast not be an lvalue. */
- if (TREE_CODE (val) == NOP_EXPR
- && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
- val = TREE_OPERAND (val, 0);
-
- if (field == 0
- || (DECL_MODE (field) != BImode))
- {
- register int fieldsize;
-
- /* An element that is not a bit-field.
- Output any buffered-up bit-fields preceding it. */
- if (byte_buffer_in_use)
- {
- ASM_OUTPUT_BYTE (asm_out_file, byte);
- total_bytes++;
- byte_buffer_in_use = 0;
- }
-
- /* Advance to offset of this element.
- Note no alignment needed in an array, since that is guaranteed
- if each element has the proper size. */
- if (field != 0 && DECL_OFFSET (field) / BITS_PER_UNIT != total_bytes)
- {
- ASM_OUTPUT_SKIP (asm_out_file,
- (DECL_OFFSET (field) / BITS_PER_UNIT
- - total_bytes));
- total_bytes = DECL_OFFSET (field) / BITS_PER_UNIT;
- }
-
- /* Determine size this element should occupy. */
- if (field)
- {
- if (! TREE_LITERAL (DECL_SIZE (field)))
- abort ();
- fieldsize = TREE_INT_CST_LOW (DECL_SIZE (field))
- * DECL_SIZE_UNIT (field);
- fieldsize = (fieldsize + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
- }
- else
- fieldsize = int_size_in_bytes (TREE_TYPE (TREE_TYPE (exp)));
-
- /* Output the element's initial value. */
- output_constant (val, fieldsize);
-
- /* Count its size. */
- total_bytes += fieldsize;
- }
- else if (TREE_CODE (val) != INTEGER_CST)
- error ("invalid initial value for member `%s'",
- IDENTIFIER_POINTER (DECL_NAME (field)));
- else
- {
- /* Element that is a bit-field. */
-
- int next_offset = DECL_OFFSET (field);
- int end_offset
- = (next_offset
- + (TREE_INT_CST_LOW (DECL_SIZE (field))
- * DECL_SIZE_UNIT (field)));
-
- /* If this field does not start in this (or, next) byte,
- skip some bytes. */
- if (next_offset / BITS_PER_UNIT != total_bytes)
- {
- /* Output remnant of any bit field in previous bytes. */
- if (byte_buffer_in_use)
- {
- ASM_OUTPUT_BYTE (asm_out_file, byte);
- total_bytes++;
- byte_buffer_in_use = 0;
- }
-
- /* If still not at proper byte, advance to there. */
- if (next_offset / BITS_PER_UNIT != total_bytes)
- {
- ASM_OUTPUT_SKIP (asm_out_file,
- next_offset / BITS_PER_UNIT - total_bytes);
- total_bytes = next_offset / BITS_PER_UNIT;
- }
- }
-
- if (! byte_buffer_in_use)
- byte = 0;
-
- /* We must split the element into pieces that fall within
- separate bytes, and combine each byte with previous or
- following bit-fields. */
-
- /* next_offset is the offset n fbits from the begining of
- the structure to the next bit of this element to be processed.
- end_offset is the offset of the first bit past the end of
- this element. */
- while (next_offset < end_offset)
- {
- int this_time;
- int next_byte = next_offset / BITS_PER_UNIT;
- int next_bit = next_offset % BITS_PER_UNIT;
-
- /* Advance from byte to byte
- within this element when necessary. */
- while (next_byte != total_bytes)
- {
- ASM_OUTPUT_BYTE (asm_out_file, byte);
- total_bytes++;
- byte = 0;
- }
-
- /* Number of bits we can process at once
- (all part of the same byte). */
- this_time = MIN (end_offset - next_offset,
- BITS_PER_UNIT - next_bit);
- #ifdef BYTES_BIG_ENDIAN
- /* On big-endian machine, take the most significant bits
- first (of the bits that are significant)
- and put them into bytes from the most significant end. */
- byte |= (((TREE_INT_CST_LOW (val)
- >> (end_offset - next_offset - this_time))
- & ((1 << this_time) - 1))
- << (BITS_PER_UNIT - this_time - next_bit));
- #else
- /* On little-endian machines,
- take first the least significant bits of the value
- and pack them starting at the least significant
- bits of the bytes. */
- byte |= ((TREE_INT_CST_LOW (val)
- >> (next_offset - DECL_OFFSET (field)))
- & ((1 << this_time) - 1)) << next_bit;
- #endif
- next_offset += this_time;
- byte_buffer_in_use = 1;
- }
- }
- }
- if (byte_buffer_in_use)
- {
- ASM_OUTPUT_BYTE (asm_out_file, byte);
- total_bytes++;
- }
- if (total_bytes < size)
- ASM_OUTPUT_SKIP (asm_out_file, size - total_bytes);
- }
-