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Diffstat (limited to 'gcc/config/1750a/1750a.c')
| -rw-r--r-- | gcc/config/1750a/1750a.c | 932 |
1 files changed, 0 insertions, 932 deletions
diff --git a/gcc/config/1750a/1750a.c b/gcc/config/1750a/1750a.c deleted file mode 100644 index c8b6a796efc..00000000000 --- a/gcc/config/1750a/1750a.c +++ /dev/null @@ -1,932 +0,0 @@ -/* Subroutines for insn-output.c for MIL-STD-1750. - Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, - 2000 Free Software Foundation, Inc. - Contributed by O.M.Kellogg, DASA (kellogg@space.otn.dasa.de) - -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 2, 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, 59 Temple Place - Suite 330, -Boston, MA 02111-1307, USA. */ - -#define __datalbl -#include "config.h" -#include "system.h" -#include "rtl.h" -#include "tree.h" -#include "function.h" -#include "expr.h" -#define HAVE_cc0 -#include "conditions.h" -#include "real.h" -#include "regs.h" -#include "output.h" -#include "flags.h" -#include "tm_p.h" -#include "target.h" -#include "target-def.h" - -struct datalabel_array datalbl[DATALBL_ARRSIZ]; -int datalbl_ndx = -1; -struct jumplabel_array jmplbl[JMPLBL_ARRSIZ]; -int jmplbl_ndx = -1; -int label_pending = 0, program_counter = 0; -enum section current_section = Normal; -const char *const sectname[4] = -{"Init", "Normal", "Konst", "Static"}; - -static int which_bit PARAMS ((int)); -static bool assemble_integer_1750a PARAMS ((rtx, unsigned int, int)); -static void output_function_prologue PARAMS ((FILE *, HOST_WIDE_INT)); -static void output_function_epilogue PARAMS ((FILE *, HOST_WIDE_INT)); - -/* Initialize the GCC target structure. */ -#undef TARGET_ASM_BYTE_OP -#define TARGET_ASM_BYTE_OP "\tdata\t" -#undef TARGET_ASM_ALIGNED_HI_OP -#define TARGET_ASM_ALIGNED_HI_OP "\tdatal\t" -#undef TARGET_ASM_ALIGNED_SI_OP -#define TARGET_ASM_ALIGNED_SI_OP NULL -#undef TARGET_ASM_INTEGER -#define TARGET_ASM_INTEGER assemble_integer_1750a - -#undef TARGET_ASM_FUNCTION_PROLOGUE -#define TARGET_ASM_FUNCTION_PROLOGUE output_function_prologue -#undef TARGET_ASM_FUNCTION_EPILOGUE -#define TARGET_ASM_FUNCTION_EPILOGUE output_function_epilogue - -struct gcc_target targetm = TARGET_INITIALIZER; - -/* Generate the assembly code for function entry. FILE is a stdio - stream to output the code to. SIZE is an int: how many units of - temporary storage to allocate. - - Refer to the array `regs_ever_live' to determine which registers to - save; `regs_ever_live[I]' is nonzero if register number I is ever - used in the function. This function is responsible for knowing - which registers should not be saved even if used. */ - -static void -output_function_prologue (file, size) - FILE *file; - HOST_WIDE_INT size; -{ - if (flag_verbose_asm) - { - int regno, regs_used = 0; - - fprintf (file, "\t; registers used: "); - for (regno = 0; regno < 14; regno++) - if (regs_ever_live[regno]) - { - fprintf (file, " %s", reg_names[regno]); - regs_used++; - } - - if (regs_used == 0) - fprintf (file, "(none)"); - } - - if (size > 0) - { - fprintf (file, "\n\t%s\tr15,%d", - (size <= 16 ? "sisp" : "sim"), size); - if (flag_verbose_asm) - fprintf (file, " ; reserve local-variable space"); - } - - if (frame_pointer_needed) - { - fprintf(file, "\n\tpshm\tr14,r14"); - if (flag_verbose_asm) - fprintf (file, " ; push old frame"); - fprintf (file, "\n\tlr\tr14,r15"); - if (flag_verbose_asm) - fprintf (file, " ; set new frame"); - } - - fprintf (file, "\n"); - program_counter = 0; - jmplbl_ndx = -1; -} - -/* This function generates the assembly code for function exit. - Args are as for output_function_prologue (). - - The function epilogue should not depend on the current stack - pointer! It should use the frame pointer only. This is mandatory - because of alloca; we also take advantage of it to omit stack - adjustments before returning. */ - -static void -output_function_epilogue (file, size) - FILE *file; - HOST_WIDE_INT size; -{ - if (frame_pointer_needed) - { - fprintf (file, "\tlr\tr15,r14"); - if (flag_verbose_asm) - fprintf (file, " ; set stack ptr to frame ptr"); - fprintf (file, "\n\tpopm\tr14,r14"); - if (flag_verbose_asm) - fprintf (file, " ; restore previous frame ptr"); - fprintf (file, "\n"); - } - - if (size > 0) - { - fprintf (file, "\t%s\tr15,%d", - (size <= 16 ? "aisp" : "aim"), size); - if (flag_verbose_asm) - fprintf (file, " ; free up local-var space"); - fprintf (file, "\n"); - } - - fprintf (file, "\turs\tr15\n\n"); -} - -void -notice_update_cc (exp) - rtx exp; -{ - if (GET_CODE (exp) == SET) - { - enum rtx_code src_code = GET_CODE (SET_SRC (exp)); - /* Jumps do not alter the cc's. */ - if (SET_DEST (exp) == pc_rtx) - return; - /* Moving a register or constant into memory doesn't alter the cc's. */ - if (GET_CODE (SET_DEST (exp)) == MEM - && (src_code == REG || src_code == CONST_INT)) - return; - /* Function calls clobber the cc's. */ - if (src_code == CALL) - { - CC_STATUS_INIT; - return; - } - /* Emulated longword bit-ops leave cc's incorrect */ - if (GET_MODE (SET_DEST (exp)) == HImode ? - src_code == AND || src_code == IOR || - src_code == XOR || src_code == NOT : 0) - { - CC_STATUS_INIT; - return; - } - /* Tests and compares set the cc's in predictable ways. */ - if (SET_DEST (exp) == cc0_rtx) - { - CC_STATUS_INIT; - cc_status.value1 = SET_SRC (exp); - return; - } - /* Anything else will set cc_status. */ - cc_status.flags = CC_NO_OVERFLOW; - cc_status.value1 = SET_SRC (exp); - cc_status.value2 = SET_DEST (exp); - return; - } - else if (GET_CODE (exp) == PARALLEL - && GET_CODE (XVECEXP (exp, 0, 0)) == SET) - { - if (SET_DEST (XVECEXP (exp, 0, 0)) == pc_rtx) - return; - if (SET_DEST (XVECEXP (exp, 0, 0)) == cc0_rtx) - { - CC_STATUS_INIT; - cc_status.value1 = SET_SRC (XVECEXP (exp, 0, 0)); - return; - } - CC_STATUS_INIT; - } - else - { - CC_STATUS_INIT; - } -} - - -rtx -function_arg (cum, mode, type, named) - int cum; - enum machine_mode mode; - tree type; - int named ATTRIBUTE_UNUSED; -{ - int size; - - if (MUST_PASS_IN_STACK (mode, type)) - return (rtx) 0; - if (mode == BLKmode) - size = int_size_in_bytes (type); - else - size = GET_MODE_SIZE (mode); - if (cum + size < 12) - return gen_rtx_REG (mode, cum); - else - return (rtx) 0; -} - -const char * -movcnt_regno_adjust (op) - rtx *op; -{ - static char outstr[80]; - int op0r = REGNO (op[0]), op1r = REGNO (op[1]), op2r = REGNO (op[2]); -#define dstreg op0r -#define srcreg op1r -#define cntreg op2r -#define cntreg_1750 (op0r + 1) - - if (cntreg == cntreg_1750) - sprintf (outstr, "mov r%d,r%d", op0r, op1r); - else if (dstreg + 1 == srcreg && cntreg > srcreg) - sprintf (outstr, "xwr r%d,r%d\n\tmov r%d,r%d", op2r, op1r, op0r, op2r); - else if (dstreg == cntreg + 1) - sprintf (outstr, "xwr r%d,r%d\n\tmov r%d,r%d", op0r, op2r, op2r, op1r); - else if (dstreg == srcreg + 1) - sprintf (outstr, "xwr r%d,r%d\n\txwr r%d,r%d\n\tmov r%d,r%d", - op0r, op1r, op0r, op2r, op1r, op2r); - else if (cntreg + 1 == srcreg) - sprintf (outstr, "xwr r%d,r%d\n\txwr r%d,r%d\n\tmov r%d,r%d", - op2r, op1r, op0r, op2r, op2r, op0r); - else if (cntreg == srcreg + 1) - sprintf (outstr, "xwr r%d,r%d\n\tmov r%d,r%d", op0r, op1r, op1r, op0r); - else - sprintf (outstr, "xwr r%d,r%d\n\tmov r%d,r%d\n\txwr r%d,r%d", - op2r, cntreg_1750, op0r, op1r, op2r, cntreg_1750); - return outstr; -} - -const char * -mod_regno_adjust (instr, op) - const char *instr; - rtx *op; -{ - static char outstr[40]; - const char *const r = (!strncmp (instr, "dvr", 3) ? "r" : ""); - int modregno_gcc = REGNO (op[3]), modregno_1750 = REGNO (op[0]) + 1; - - if (modregno_gcc == modregno_1750 - || (reg_renumber != NULL - && reg_renumber[modregno_gcc] >= 0 - && reg_renumber[modregno_gcc] == reg_renumber[modregno_1750])) - sprintf (outstr, "%s r%%0,%s%%2", instr, r); - else - sprintf (outstr, "lr r%d,r%d\n\t%s r%%0,%s%%2\n\txwr r%d,r%d", - modregno_gcc, modregno_1750, instr, r, modregno_1750, - modregno_gcc); - return outstr; -} - - -/* Check if op is a valid memory operand for 1750A Load/Store instructions - (memory indirection permitted.) */ - -int -memop_valid (op) - rtx op; -{ - static int recurred = 0; - int valid_operand; - - if (GET_MODE (op) != Pmode && GET_MODE (op) != VOIDmode - && GET_MODE (op) != QImode) - return 0; - switch (GET_CODE (op)) - { - case MEM: - if (!recurred && GET_CODE (XEXP (op, 0)) == REG) - return 1; - case MINUS: - case MULT: - case DIV: - return 0; - case PLUS: - recurred = 1; - valid_operand = memop_valid (XEXP (op, 0)); - if (valid_operand) - valid_operand = memop_valid (XEXP (op, 1)); - recurred = 0; - return valid_operand; - case REG: - if (REGNO (op) > 0) - return 1; - return 0; - case CONST: - case CONST_INT: - case SYMBOL_REF: - case SUBREG: - return 1; - default: - printf ("memop_valid: code=%d\n", (int) GET_CODE (op)); - return 1; - } -} - - -/* predicate for the MOV instruction: */ -int -mov_memory_operand (op, mode) - rtx op; - enum machine_mode mode ATTRIBUTE_UNUSED; -{ - return (GET_CODE (op) == MEM && GET_CODE (XEXP (op, 0)) == REG); -} - -/* predicate for the STC instruction: */ -int -small_nonneg_const (op, mode) - rtx op; - enum machine_mode mode ATTRIBUTE_UNUSED; -{ - if (GET_CODE (op) == CONST_INT && INTVAL (op) >= 0 && INTVAL (op) <= 15) - return 1; - return 0; -} - -/* predicate for constant zero: */ -int -zero_operand (op, mode) - rtx op; - enum machine_mode mode; -{ - return op == CONST0_RTX (mode); -} - - -/* predicate for 1750 `B' addressing mode (Base Register with Offset) - memory operand */ -int -b_mode_operand (op) - rtx op; -{ - if (GET_CODE (op) == MEM) - { - rtx inner = XEXP (op, 0); - if (GET_CODE (inner) == REG && REG_OK_FOR_INDEX_P (inner)) - return 1; - if (GET_CODE (inner) == PLUS) - { - rtx plus_op0 = XEXP (inner, 0); - if (GET_CODE (plus_op0) == REG && REG_OK_FOR_INDEX_P (plus_op0)) - { - rtx plus_op1 = XEXP (inner, 1); - if (GET_CODE (plus_op1) == CONST_INT - && INTVAL (plus_op1) >= 0 - && INTVAL (plus_op1) <= 255) - return 1; - } - } - } - return 0; -} - - -/* Decide whether to output a conditional jump as a "Jump Conditional" - or as a "Branch Conditional": */ - -int -find_jmplbl (labelnum) - int labelnum; -{ - int i, found = 0; - - for (i = 0; i <= jmplbl_ndx; i++) - if (labelnum == jmplbl[i].num) - { - found = 1; - break; - } - if (found) - return i; - return -1; -} - -const char * -branch_or_jump (condition, targetlabel_number) - const char *condition; - int targetlabel_number; -{ - static char buf[30]; - int index; - - if ((index = find_jmplbl (targetlabel_number)) >= 0) - if (program_counter - jmplbl[index].pc < 128) - { - sprintf (buf, "b%s %%l0", condition); - return buf; - } - sprintf (buf, "jc %s,%%l0", condition); - return buf; -} - - -int -unsigned_comparison_operator (insn) - rtx insn; -{ - switch (GET_CODE (insn)) - { - case GEU: - case GTU: - case LEU: - case LTU: - return 1; - default: - return 0; - } -} - -int -next_cc_user_is_unsigned (insn) - rtx insn; -{ - if ( !(insn = next_cc0_user (insn))) - abort (); - else if (GET_CODE (insn) == JUMP_INSN - && GET_CODE (PATTERN (insn)) == SET - && GET_CODE (SET_SRC (PATTERN (insn))) == IF_THEN_ELSE) - return unsigned_comparison_operator (XEXP (SET_SRC (PATTERN (insn)), 0)); - else if (GET_CODE (insn) == INSN - && GET_CODE (PATTERN (insn)) == SET) - return unsigned_comparison_operator (SET_SRC (PATTERN (insn))); - else - abort (); -} - - -static int addr_inc; - -/* A C compound statement to output to stdio stream STREAM the - assembler syntax for an instruction operand X. X is an RTL - expression. - - CODE is a value that can be used to specify one of several ways - of printing the operand. It is used when identical operands - must be printed differently depending on the context. CODE - comes from the `%' specification that was used to request - printing of the operand. If the specification was just `%DIGIT' - then CODE is 0; if the specification was `%LTR DIGIT' then CODE - is the ASCII code for LTR. - - If X is a register, this macro should print the register's name. - The names can be found in an array `reg_names' whose type is - `char *[]'. `reg_names' is initialized from `REGISTER_NAMES'. - - When the machine description has a specification `%PUNCT' (a `%' - followed by a punctuation character), this macro is called with - a null pointer for X and the punctuation character for CODE. - - The 1750 specific codes are: - 'J' for the negative of a constant - 'Q' for printing addresses in B mode syntax - 'd' for the second register in a pair - 't' for the third register in a triple - 'b' for the bit number (using 1750 test bit convention) - 'B' for the bit number of the 1's complement (for bit clear) - 'w' for int - 16 -*/ - -void -print_operand (file, x, letter) - FILE *file; - rtx x; - int letter; -{ - switch (GET_CODE (x)) - { - case REG: - if (letter == 'd') - fprintf (file, "%d", REGNO (x) + 1); - else if (letter == 't') - fprintf (file, "%d", REGNO (x) + 2); - else - fprintf (file, "%d", REGNO (x)); - break; - - case SYMBOL_REF: - fprintf (file, "%s", XSTR (x, 0)); - if (letter == 'A') - fprintf (file, "+1"); - break; - - case LABEL_REF: - case CONST: - case MEM: - if (letter == 'Q') - { - rtx inner = XEXP (x, 0); - switch (GET_CODE (inner)) - { - case REG: - fprintf (file, "r%d,0", REGNO (inner)); - break; - case PLUS: - fprintf (file, "r%d,%d", REGNO (XEXP (inner, 0)), - INTVAL (XEXP (inner, 1))); - break; - default: - fprintf (file, "[ill Q code=%d]", GET_CODE (inner)); - } - } - else - { - addr_inc = (letter == 'A' ? 1 : 0); - output_address (XEXP (x, 0)); - } - break; - - case CONST_DOUBLE: - { - REAL_VALUE_TYPE r; - char buf[30]; - - REAL_VALUE_FROM_CONST_DOUBLE (r, x); - REAL_VALUE_TO_DECIMAL (r, "%f", buf); - - fputs (buf, file); - } - break; - - case CONST_INT: - if (letter == 'J') - fprintf (file, HOST_WIDE_INT_PRINT_DEC, -INTVAL (x)); - else if (letter == 'b') - fprintf (file, "%d", which_bit (INTVAL (x))); - else if (letter == 'B') - fprintf (file, "%d", which_bit (~INTVAL (x))); - else if (letter == 'w') - fprintf (file, HOST_WIDE_INT_PRINT_DEC, INTVAL (x) - 16); - else - fprintf (file, HOST_WIDE_INT_PRINT_DEC, INTVAL (x)); - break; - - case CODE_LABEL: - fprintf (file, "L%d", XINT (x, 3)); - break; - - case CALL: - fprintf (file, "CALL nargs="); - fprintf (file, HOST_PTR_PRINTF, (PTR) XEXP (x, 1)); - fprintf (file, ", func is either '%s' or '%s'", - XSTR (XEXP (XEXP (x, 0), 1), 0), XSTR (XEXP (x, 0), 1)); - break; - - case PLUS: - { - rtx op0 = XEXP (x, 0), op1 = XEXP (x, 1); - int op0code = GET_CODE (op0), op1code = GET_CODE (op1); - if (op1code == CONST_INT) - switch (op0code) - { - case REG: - fprintf (file, "%d,r%d ; p_o_PLUS for REG and CONST_INT", - INTVAL (op1), REGNO (op0)); - break; - case SYMBOL_REF: - fprintf (file, "%d+%s", INTVAL (op1), XSTR (op0, 0)); - break; - case MEM: - fprintf (file, "%d,[mem:", INTVAL (op1)); - output_address (XEXP (op0, 0)); - fprintf (file, "] ;P_O plus"); - break; - default: - fprintf (file, "p_o_PLUS UFO, code=%d, with CONST=%d", - (int) op0code, INTVAL (op1)); - } - else if (op1code == SYMBOL_REF && op0code == REG) - fprintf (file, "%s,r%d ; P_O: (plus reg sym)", - XSTR (op1, 0), REGNO (op0)); - else - fprintf (file, "p_o_+: op0code=%d, op1code=%d", op0code, op1code); - } - break; - - default: - fprintf (file, "p_o_UFO code=%d", GET_CODE (x)); - } - - addr_inc = 0; -} - -void -print_operand_address (file, addr) - FILE *file; - rtx addr; -{ - switch (GET_CODE (addr)) - { - case REG: - fprintf (file, "%d,r%d ; P_O_A", addr_inc, REGNO (addr)); - break; - case PLUS: - { - register rtx x = XEXP (addr, 0), y = XEXP (addr, 1); - switch (GET_CODE (x)) - { - case REG: - switch (GET_CODE (y)) - { - case CONST: - output_address (XEXP (y, 0)); - fprintf (file, ",r%d ;P_O_A reg + const expr", REGNO (x)); - break; - case CONST_INT: - fprintf (file, "%d,r%d", INTVAL (y) + addr_inc, REGNO (x)); - break; - case SYMBOL_REF: - fprintf (file, "%s", XSTR (y, 0)); - if (addr_inc) - fprintf (file, "+%d", addr_inc); - fprintf (file, ",r%d ; P_O_A reg + sym", REGNO (x)); - break; - case LABEL_REF: - output_address (XEXP (y, 0)); - fprintf (file, ",r%d ; P_O_A reg + label", REGNO (x)); - break; - default: - fprintf (file, "[P_O_A reg%d+UFO code=%d]", - REGNO (x), GET_CODE (y)); - } - break; - case LABEL_REF: - output_address (XEXP (x, 0)); - break; - case SYMBOL_REF: - switch (GET_CODE (y)) - { - case CONST_INT: - fprintf (file, "%d+%s", INTVAL (y) + addr_inc, XSTR (x, 0)); - break; - case REG: - fprintf (file, "%s,r%d ;P_O_A sym + reg", - XSTR (x, 0), REGNO (y)); - break; - default: - fprintf (file, "P_O_A sym/lab+UFO[sym=%s,code(y)=%d]", - XSTR (x, 0), GET_CODE (y)); - } - break; - case CONST: - output_address (XEXP (x, 0)); - if (GET_CODE (y) == REG) - fprintf (file, ",r%d ;P_O_A const + reg", REGNO (x)); - else - fprintf (file, "P_O_A const+UFO code(y)=%d]", GET_CODE (y)); - break; - case MEM: - output_address (y); - fprintf (file, ",[mem:"); - output_address (XEXP (x, 0)); - fprintf (file, "] ;P_O_A plus"); - break; - default: - fprintf (file, "P_O_A plus op1_UFO[code1=%d,code2=%d]", - GET_CODE (x), GET_CODE (y)); - } - } - break; - case CONST_INT: - if (INTVAL (addr) < 0x10000 && INTVAL (addr) >= -0x10000) - fprintf (file, "%d ; p_o_a const addr?!", INTVAL (addr)); - else - { - fprintf (file, "[p_o_a=ILLEGAL_CONST]"); - output_addr_const (file, addr); - } - break; - case LABEL_REF: - case SYMBOL_REF: - fprintf (file, "%s", XSTR (addr, 0)); - if (addr_inc) - fprintf (file, "+%d", addr_inc); - break; - case MEM: - fprintf (file, "[memUFO:"); - output_address (XEXP (addr, 0)); - fprintf (file, "]"); - break; - case CONST: - output_address (XEXP (addr, 0)); - fprintf (file, " ;P_O_A const"); - break; - case CODE_LABEL: - fprintf (file, "L%d", XINT (addr, 3)); - break; - default: - fprintf (file, " p_o_a UFO, code=%d val=0x%x", - (int) GET_CODE (addr), INTVAL (addr)); - break; - } - addr_inc = 0; -} - -/* Target hook for assembling integer objects. The 1750a version needs to - keep track of how many bytes have been written. */ - -static bool -assemble_integer_1750a (x, size, aligned_p) - rtx x; - unsigned int size; - int aligned_p; -{ - if (default_assemble_integer (x, size, aligned_p)) - { - if (label_pending) - label_pending = 0; - datalbl[datalbl_ndx].size += size; - return true; - } - return false; -} - - -/* - * Return non zero if the LS 16 bits of the given value has just one bit set, - * otherwise return zero. Note this function may be used to detect one - * bit clear by inverting the param. - */ -int -one_bit_set_p (x) - int x; -{ - x &= 0xffff; - return x && (x & (x - 1)) == 0; -} - - -/* - * Return the number of the least significant bit set, using the same - * convention for bit numbering as in the MIL-STD-1750 sb instruction. - */ -static int -which_bit (x) - int x; -{ - int b = 15; - - while (b > 0 && (x & 1) == 0) - { - b--; - x >>= 1; - } - - return b; -} - - -/* Convert a REAL_VALUE_TYPE to the target float format: - - MSB LSB MSB LSB - ------------------------------------------------------ - |S| Mantissa | Exponent | - ------------------------------------------------------ - 0 1 23 24 31 - -*/ - -long -real_value_to_target_single(in) - REAL_VALUE_TYPE in; -{ - union { - double d; - struct { -#if HOST_WORDS_BIG_ENDIAN - unsigned int negative:1; - unsigned int exponent:11; - unsigned int mantissa0:20; - unsigned int mantissa1:32; -#else - unsigned int mantissa1:32; - unsigned int mantissa0:20; - unsigned int exponent:11; - unsigned int negative:1; -#endif - } s; - } ieee; - - unsigned int mant; - int exp; - - if (HOST_FLOAT_FORMAT != IEEE_FLOAT_FORMAT) - abort (); - - ieee.d = in; - - /* Don't bother with NaN, Inf, 0 special cases, since they'll be handled - by the over/underflow code below. */ - exp = ieee.s.exponent - 0x3ff; - mant = 1 << 23 | ieee.s.mantissa0 << 3 | ieee.s.mantissa1 >> 29; - - /* The sign is actually part of the mantessa. Since we're comming from - IEEE we know that either bit 23 is set or we have a zero. */ - if (! ieee.s.negative) - { - mant >>= 1; - exp += 1; - } - - /* Check for overflow. Crop to FLT_MAX. */ - if (exp > 127) - { - exp = 127; - mant = (ieee.s.negative ? 0xffffff : 0x7fffff); - } - /* Underflow to zero. */ - else if (exp < -128) - { - exp = 0; - mant = 0; - } - - return mant << 8 | (exp & 0xff); -} - -/* Convert a REAL_VALUE_TYPE to the target 1750a extended float format: - - ---------------------------------------------------- - | | Mantissa | | Mantissa | - |S| MS |Exponent| LS | - ---------------------------------------------------- - 0 1 23 24 31 32 47 - -*/ - -void -real_value_to_target_double(in, out) - REAL_VALUE_TYPE in; - long out[]; -{ - union { - double d; - struct { -#if HOST_WORDS_BIG_ENDIAN - unsigned int negative:1; - unsigned int exponent:11; - unsigned int mantissa0:20; - unsigned int mantissa1:32; -#else - unsigned int mantissa1:32; - unsigned int mantissa0:20; - unsigned int exponent:11; - unsigned int negative:1; -#endif - } s; - } ieee; - - unsigned int mant_h24, mant_l16; - int exp; - - if (HOST_FLOAT_FORMAT != IEEE_FLOAT_FORMAT) - abort (); - - ieee.d = in; - - /* Don't bother with NaN, Inf, 0 special cases, since they'll be handled - by the over/underflow code below. */ - exp = ieee.s.exponent - 0x3ff; - mant_h24 = 1 << 23 | ieee.s.mantissa0 << 3 | ieee.s.mantissa1 >> 29; - mant_l16 = (ieee.s.mantissa1 >> 13) & 0xffff; - - /* The sign is actually part of the mantessa. Since we're comming from - IEEE we know that either bit 23 is set or we have a zero. */ - if (! ieee.s.negative) - { - mant_l16 = mant_l16 >> 1 | (mant_h24 & 1) << 15; - mant_h24 >>= 1; - exp += 1; - } - - /* Check for overflow. Crop to DBL_MAX. */ - if (exp > 127) - { - exp = 127; - mant_h24 = (ieee.s.negative ? 0xffffff : 0x7fffff); - mant_l16 = 0xffff; - } - /* Underflow to zero. */ - else if (exp < -128) - { - exp = 0; - mant_h24 = 0; - mant_l16 = 0; - } - - out[0] = mant_h24 << 8 | (exp & 0xff); - out[1] = mant_l16; -} |