diff options
Diffstat (limited to 'contrib/gcc/jump.c')
| -rw-r--r-- | contrib/gcc/jump.c | 92 |
1 files changed, 44 insertions, 48 deletions
diff --git a/contrib/gcc/jump.c b/contrib/gcc/jump.c index f60e16967f3b..fffc8e7cbb1f 100644 --- a/contrib/gcc/jump.c +++ b/contrib/gcc/jump.c @@ -1,6 +1,6 @@ /* Optimize jump instructions, for GNU compiler. Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997 - 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc. + 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc. This file is part of GCC. @@ -328,8 +328,6 @@ duplicate_loop_exit_test (loop_start) is a CODE_LABEL has a REG_RETVAL or REG_LIBCALL note (hard to adjust) is a NOTE_INSN_LOOP_BEG because this means we have a nested loop - is a NOTE_INSN_BLOCK_{BEG,END} because duplicating these notes - is not valid. We also do not do this if we find an insn with ASM_OPERANDS. While this restriction should not be necessary, copying an insn with @@ -349,18 +347,6 @@ duplicate_loop_exit_test (loop_start) case CALL_INSN: return 0; case NOTE: - /* We could be in front of the wrong NOTE_INSN_LOOP_END if there is - a jump immediately after the loop start that branches outside - the loop but within an outer loop, near the exit test. - If we copied this exit test and created a phony - NOTE_INSN_LOOP_VTOP, this could make instructions immediately - before the exit test look like these could be safely moved - out of the loop even if they actually may be never executed. - This can be avoided by checking here for NOTE_INSN_LOOP_CONT. */ - - if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG - || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_CONT) - return 0; if (optimize < 2 && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG @@ -446,6 +432,7 @@ duplicate_loop_exit_test (loop_start) replace_regs (PATTERN (copy), reg_map, max_reg, 1); mark_jump_label (PATTERN (copy), copy, 0); + INSN_SCOPE (copy) = INSN_SCOPE (insn); /* Copy all REG_NOTES except REG_LABEL since mark_jump_label will make them. */ @@ -471,6 +458,7 @@ duplicate_loop_exit_test (loop_start) case JUMP_INSN: copy = emit_jump_insn_before (copy_insn (PATTERN (insn)), loop_start); + INSN_SCOPE (copy) = INSN_SCOPE (insn); if (reg_map) replace_regs (PATTERN (copy), reg_map, max_reg, 1); mark_jump_label (PATTERN (copy), copy, 0); @@ -720,11 +708,6 @@ reversed_comparison_code_parts (code, arg0, arg1, insn) break; } - /* In case we give up IEEE compatibility, all comparisons are reversible. */ - if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT - || flag_unsafe_math_optimizations) - return reverse_condition (code); - if (GET_MODE_CLASS (mode) == MODE_CC #ifdef HAVE_cc0 || arg0 == cc0_rtx @@ -773,11 +756,12 @@ reversed_comparison_code_parts (code, arg0, arg1, insn) } } - /* An integer condition. */ + /* Test for an integer condition, or a floating-point comparison + in which NaNs can be ignored. */ if (GET_CODE (arg0) == CONST_INT || (GET_MODE (arg0) != VOIDmode && GET_MODE_CLASS (mode) != MODE_CC - && ! FLOAT_MODE_P (mode))) + && !HONOR_NANS (mode))) return reverse_condition (code); return UNKNOWN; @@ -856,10 +840,6 @@ enum rtx_code reverse_condition_maybe_unordered (code) enum rtx_code code; { - /* Non-IEEE formats don't have unordered conditions. */ - if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT) - return reverse_condition (code); - switch (code) { case EQ: @@ -1005,7 +985,7 @@ signed_condition (code) } } -/* Return non-zero if CODE1 is more strict than CODE2, i.e., if the +/* Return nonzero if CODE1 is more strict than CODE2, i.e., if the truth of CODE1 implies the truth of CODE2. */ int @@ -1099,6 +1079,7 @@ simplejump_p (insn) && GET_CODE (SET_DEST (PATTERN (insn))) == PC && GET_CODE (SET_SRC (PATTERN (insn))) == LABEL_REF); } + /* Return 1 if INSN is an tablejump. */ int @@ -1107,12 +1088,12 @@ tablejump_p (insn) { rtx table; return (GET_CODE (insn) == JUMP_INSN - && JUMP_LABEL (insn) - && NEXT_INSN (JUMP_LABEL (insn)) - && (table = next_active_insn (JUMP_LABEL (insn))) - && GET_CODE (table) == JUMP_INSN - && (GET_CODE (PATTERN (table)) == ADDR_VEC - || GET_CODE (PATTERN (table)) == ADDR_DIFF_VEC)); + && JUMP_LABEL (insn) + && NEXT_INSN (JUMP_LABEL (insn)) + && (table = next_active_insn (JUMP_LABEL (insn))) + && GET_CODE (table) == JUMP_INSN + && (GET_CODE (PATTERN (table)) == ADDR_VEC + || GET_CODE (PATTERN (table)) == ADDR_DIFF_VEC)); } /* Return nonzero if INSN is a (possibly) conditional jump @@ -1313,7 +1294,7 @@ onlyjump_p (insn) #ifdef HAVE_cc0 -/* Return non-zero if X is an RTX that only sets the condition codes +/* Return nonzero if X is an RTX that only sets the condition codes and has no side effects. */ int @@ -1455,7 +1436,6 @@ mark_jump_label (x, insn, in_mem) case PC: case CC0: case REG: - case SUBREG: case CONST_INT: case CONST_DOUBLE: case CLOBBER: @@ -1598,7 +1578,9 @@ delete_prior_computation (note, insn) break; /* If we reach a SEQUENCE, it is too complex to try to - do anything with it, so give up. */ + do anything with it, so give up. We can be run during + and after reorg, so SEQUENCE rtl can legitimately show + up here. */ if (GET_CODE (pat) == SEQUENCE) break; @@ -1934,14 +1916,14 @@ delete_for_peephole (from, to) is also an unconditional jump in that case. */ } -/* We have determined that INSN is never reached, and are about to - delete it. Print a warning if the user asked for one. +/* We have determined that AVOIDED_INSN is never reached, and are + about to delete it. If the insn chain between AVOIDED_INSN and + FINISH contains more than one line from the current function, and + contains at least one operation, print a warning if the user asked + for it. If FINISH is NULL, look between AVOIDED_INSN and a LABEL. - To try to make this warning more useful, this should only be called - once per basic block not reached, and it only warns when the basic - block contains more than one line from the current function, and - contains at least one operation. CSE and inlining can duplicate insns, - so it's possible to get spurious warnings from this. */ + CSE and inlining can duplicate insns, so it's possible to get + spurious warnings from this. */ void never_reached_warning (avoided_insn, finish) @@ -1951,15 +1933,29 @@ never_reached_warning (avoided_insn, finish) rtx a_line_note = NULL; int two_avoided_lines = 0, contains_insn = 0, reached_end = 0; - if (! warn_notreached) + if (!warn_notreached) return; - /* Scan forwards, looking at LINE_NUMBER notes, until - we hit a LABEL or we run out of insns. */ + /* Back up to the first of any NOTEs preceding avoided_insn; flow passes + us the head of a block, a NOTE_INSN_BASIC_BLOCK, which often follows + the line note. */ + insn = avoided_insn; + while (1) + { + rtx prev = PREV_INSN (insn); + if (prev == NULL_RTX + || GET_CODE (prev) != NOTE) + break; + insn = prev; + } + + /* Scan forwards, looking at LINE_NUMBER notes, until we hit a LABEL + in case FINISH is NULL, otherwise until we run out of insns. */ - for (insn = avoided_insn; insn != NULL; insn = NEXT_INSN (insn)) + for (; insn != NULL; insn = NEXT_INSN (insn)) { - if (finish == NULL && GET_CODE (insn) == CODE_LABEL) + if ((finish == NULL && GET_CODE (insn) == CODE_LABEL) + || GET_CODE (insn) == BARRIER) break; if (GET_CODE (insn) == NOTE /* A line number note? */ |