| /* Convert tree expression to rtl instructions, for GNU compiler. |
| Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, |
| 2000, 2001, 2002, 2003 Free Software Foundation, Inc. |
| |
| This file is part of GCC. |
| |
| GCC 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. |
| |
| GCC 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 GCC; see the file COPYING. If not, write to the Free |
| Software Foundation, 59 Temple Place - Suite 330, Boston, MA |
| 02111-1307, USA. */ |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "tm.h" |
| #include "rtl.h" |
| #include "tree.h" |
| #include "flags.h" |
| #include "function.h" |
| #include "insn-config.h" |
| #include "insn-attr.h" |
| /* Include expr.h after insn-config.h so we get HAVE_conditional_move. */ |
| #include "expr.h" |
| #include "optabs.h" |
| #include "langhooks.h" |
| |
| static void do_jump_by_parts_greater (tree, int, rtx, rtx); |
| static void do_jump_by_parts_equality (tree, rtx, rtx); |
| static void do_compare_and_jump (tree, enum rtx_code, enum rtx_code, rtx, |
| rtx); |
| |
| /* At the start of a function, record that we have no previously-pushed |
| arguments waiting to be popped. */ |
| |
| void |
| init_pending_stack_adjust (void) |
| { |
| pending_stack_adjust = 0; |
| } |
| |
| /* When exiting from function, if safe, clear out any pending stack adjust |
| so the adjustment won't get done. |
| |
| Note, if the current function calls alloca, then it must have a |
| frame pointer regardless of the value of flag_omit_frame_pointer. */ |
| |
| void |
| clear_pending_stack_adjust (void) |
| { |
| if (optimize > 0 |
| && (! flag_omit_frame_pointer || current_function_calls_alloca) |
| && EXIT_IGNORE_STACK |
| && ! (DECL_INLINE (current_function_decl) && ! flag_no_inline) |
| && ! flag_inline_functions) |
| { |
| stack_pointer_delta -= pending_stack_adjust, |
| pending_stack_adjust = 0; |
| } |
| } |
| |
| /* Pop any previously-pushed arguments that have not been popped yet. */ |
| |
| void |
| do_pending_stack_adjust (void) |
| { |
| if (inhibit_defer_pop == 0) |
| { |
| if (pending_stack_adjust != 0) |
| adjust_stack (GEN_INT (pending_stack_adjust)); |
| pending_stack_adjust = 0; |
| } |
| } |
| |
| /* Expand conditional expressions. */ |
| |
| /* Generate code to evaluate EXP and jump to LABEL if the value is zero. |
| LABEL is an rtx of code CODE_LABEL, in this function and all the |
| functions here. */ |
| |
| void |
| jumpifnot (tree exp, rtx label) |
| { |
| do_jump (exp, label, NULL_RTX); |
| } |
| |
| /* Generate code to evaluate EXP and jump to LABEL if the value is nonzero. */ |
| |
| void |
| jumpif (tree exp, rtx label) |
| { |
| do_jump (exp, NULL_RTX, label); |
| } |
| |
| /* Generate code to evaluate EXP and jump to IF_FALSE_LABEL if |
| the result is zero, or IF_TRUE_LABEL if the result is one. |
| Either of IF_FALSE_LABEL and IF_TRUE_LABEL may be zero, |
| meaning fall through in that case. |
| |
| do_jump always does any pending stack adjust except when it does not |
| actually perform a jump. An example where there is no jump |
| is when EXP is `(foo (), 0)' and IF_FALSE_LABEL is null. |
| |
| This function is responsible for optimizing cases such as |
| &&, || and comparison operators in EXP. */ |
| |
| void |
| do_jump (tree exp, rtx if_false_label, rtx if_true_label) |
| { |
| enum tree_code code = TREE_CODE (exp); |
| /* Some cases need to create a label to jump to |
| in order to properly fall through. |
| These cases set DROP_THROUGH_LABEL nonzero. */ |
| rtx drop_through_label = 0; |
| rtx temp; |
| int i; |
| tree type; |
| enum machine_mode mode; |
| |
| emit_queue (); |
| |
| switch (code) |
| { |
| case ERROR_MARK: |
| break; |
| |
| case INTEGER_CST: |
| temp = integer_zerop (exp) ? if_false_label : if_true_label; |
| if (temp) |
| emit_jump (temp); |
| break; |
| |
| #if 0 |
| /* This is not true with #pragma weak */ |
| case ADDR_EXPR: |
| /* The address of something can never be zero. */ |
| if (if_true_label) |
| emit_jump (if_true_label); |
| break; |
| #endif |
| |
| case UNSAVE_EXPR: |
| do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label); |
| TREE_OPERAND (exp, 0) |
| = (*lang_hooks.unsave_expr_now) (TREE_OPERAND (exp, 0)); |
| break; |
| |
| case NOP_EXPR: |
| if (TREE_CODE (TREE_OPERAND (exp, 0)) == COMPONENT_REF |
| || TREE_CODE (TREE_OPERAND (exp, 0)) == BIT_FIELD_REF |
| || TREE_CODE (TREE_OPERAND (exp, 0)) == ARRAY_REF |
| || TREE_CODE (TREE_OPERAND (exp, 0)) == ARRAY_RANGE_REF) |
| goto normal; |
| case CONVERT_EXPR: |
| /* If we are narrowing the operand, we have to do the compare in the |
| narrower mode. */ |
| if ((TYPE_PRECISION (TREE_TYPE (exp)) |
| < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0))))) |
| goto normal; |
| case NON_LVALUE_EXPR: |
| case REFERENCE_EXPR: |
| case ABS_EXPR: |
| case NEGATE_EXPR: |
| case LROTATE_EXPR: |
| case RROTATE_EXPR: |
| /* These cannot change zero->nonzero or vice versa. */ |
| do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label); |
| break; |
| |
| case WITH_RECORD_EXPR: |
| /* Put the object on the placeholder list, recurse through our first |
| operand, and pop the list. */ |
| placeholder_list = tree_cons (TREE_OPERAND (exp, 1), NULL_TREE, |
| placeholder_list); |
| do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label); |
| placeholder_list = TREE_CHAIN (placeholder_list); |
| break; |
| |
| #if 0 |
| /* This is never less insns than evaluating the PLUS_EXPR followed by |
| a test and can be longer if the test is eliminated. */ |
| case PLUS_EXPR: |
| /* Reduce to minus. */ |
| exp = build (MINUS_EXPR, TREE_TYPE (exp), |
| TREE_OPERAND (exp, 0), |
| fold (build1 (NEGATE_EXPR, TREE_TYPE (TREE_OPERAND (exp, 1)), |
| TREE_OPERAND (exp, 1)))); |
| /* Process as MINUS. */ |
| #endif |
| |
| case MINUS_EXPR: |
| /* Nonzero iff operands of minus differ. */ |
| do_compare_and_jump (build (NE_EXPR, TREE_TYPE (exp), |
| TREE_OPERAND (exp, 0), |
| TREE_OPERAND (exp, 1)), |
| NE, NE, if_false_label, if_true_label); |
| break; |
| |
| case BIT_AND_EXPR: |
| /* If we are AND'ing with a small constant, do this comparison in the |
| smallest type that fits. If the machine doesn't have comparisons |
| that small, it will be converted back to the wider comparison. |
| This helps if we are testing the sign bit of a narrower object. |
| combine can't do this for us because it can't know whether a |
| ZERO_EXTRACT or a compare in a smaller mode exists, but we do. */ |
| |
| if (! SLOW_BYTE_ACCESS |
| && TREE_CODE (TREE_OPERAND (exp, 1)) == INTEGER_CST |
| && TYPE_PRECISION (TREE_TYPE (exp)) <= HOST_BITS_PER_WIDE_INT |
| && (i = tree_floor_log2 (TREE_OPERAND (exp, 1))) >= 0 |
| && (mode = mode_for_size (i + 1, MODE_INT, 0)) != BLKmode |
| && (type = (*lang_hooks.types.type_for_mode) (mode, 1)) != 0 |
| && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (exp)) |
| && (cmp_optab->handlers[(int) TYPE_MODE (type)].insn_code |
| != CODE_FOR_nothing)) |
| { |
| do_jump (convert (type, exp), if_false_label, if_true_label); |
| break; |
| } |
| goto normal; |
| |
| case TRUTH_NOT_EXPR: |
| do_jump (TREE_OPERAND (exp, 0), if_true_label, if_false_label); |
| break; |
| |
| case TRUTH_ANDIF_EXPR: |
| if (if_false_label == 0) |
| if_false_label = drop_through_label = gen_label_rtx (); |
| do_jump (TREE_OPERAND (exp, 0), if_false_label, NULL_RTX); |
| start_cleanup_deferral (); |
| do_jump (TREE_OPERAND (exp, 1), if_false_label, if_true_label); |
| end_cleanup_deferral (); |
| break; |
| |
| case TRUTH_ORIF_EXPR: |
| if (if_true_label == 0) |
| if_true_label = drop_through_label = gen_label_rtx (); |
| do_jump (TREE_OPERAND (exp, 0), NULL_RTX, if_true_label); |
| start_cleanup_deferral (); |
| do_jump (TREE_OPERAND (exp, 1), if_false_label, if_true_label); |
| end_cleanup_deferral (); |
| break; |
| |
| case COMPOUND_EXPR: |
| push_temp_slots (); |
| expand_expr (TREE_OPERAND (exp, 0), const0_rtx, VOIDmode, 0); |
| preserve_temp_slots (NULL_RTX); |
| free_temp_slots (); |
| pop_temp_slots (); |
| emit_queue (); |
| do_pending_stack_adjust (); |
| do_jump (TREE_OPERAND (exp, 1), if_false_label, if_true_label); |
| break; |
| |
| case COMPONENT_REF: |
| case BIT_FIELD_REF: |
| case ARRAY_REF: |
| case ARRAY_RANGE_REF: |
| { |
| HOST_WIDE_INT bitsize, bitpos; |
| int unsignedp; |
| enum machine_mode mode; |
| tree type; |
| tree offset; |
| int volatilep = 0; |
| |
| /* Get description of this reference. We don't actually care |
| about the underlying object here. */ |
| get_inner_reference (exp, &bitsize, &bitpos, &offset, &mode, |
| &unsignedp, &volatilep); |
| |
| type = (*lang_hooks.types.type_for_size) (bitsize, unsignedp); |
| if (! SLOW_BYTE_ACCESS |
| && type != 0 && bitsize >= 0 |
| && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (exp)) |
| && (cmp_optab->handlers[(int) TYPE_MODE (type)].insn_code |
| != CODE_FOR_nothing)) |
| { |
| do_jump (convert (type, exp), if_false_label, if_true_label); |
| break; |
| } |
| goto normal; |
| } |
| |
| case COND_EXPR: |
| /* Do (a ? 1 : 0) and (a ? 0 : 1) as special cases. */ |
| if (integer_onep (TREE_OPERAND (exp, 1)) |
| && integer_zerop (TREE_OPERAND (exp, 2))) |
| do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label); |
| |
| else if (integer_zerop (TREE_OPERAND (exp, 1)) |
| && integer_onep (TREE_OPERAND (exp, 2))) |
| do_jump (TREE_OPERAND (exp, 0), if_true_label, if_false_label); |
| |
| else |
| { |
| rtx label1 = gen_label_rtx (); |
| drop_through_label = gen_label_rtx (); |
| |
| do_jump (TREE_OPERAND (exp, 0), label1, NULL_RTX); |
| |
| start_cleanup_deferral (); |
| /* Now the THEN-expression. */ |
| do_jump (TREE_OPERAND (exp, 1), |
| if_false_label ? if_false_label : drop_through_label, |
| if_true_label ? if_true_label : drop_through_label); |
| /* In case the do_jump just above never jumps. */ |
| do_pending_stack_adjust (); |
| emit_label (label1); |
| |
| /* Now the ELSE-expression. */ |
| do_jump (TREE_OPERAND (exp, 2), |
| if_false_label ? if_false_label : drop_through_label, |
| if_true_label ? if_true_label : drop_through_label); |
| end_cleanup_deferral (); |
| } |
| break; |
| |
| case EQ_EXPR: |
| { |
| tree inner_type = TREE_TYPE (TREE_OPERAND (exp, 0)); |
| |
| if (GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_COMPLEX_FLOAT |
| || GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_COMPLEX_INT) |
| { |
| tree exp0 = save_expr (TREE_OPERAND (exp, 0)); |
| tree exp1 = save_expr (TREE_OPERAND (exp, 1)); |
| do_jump |
| (fold |
| (build (TRUTH_ANDIF_EXPR, TREE_TYPE (exp), |
| fold (build (EQ_EXPR, TREE_TYPE (exp), |
| fold (build1 (REALPART_EXPR, |
| TREE_TYPE (inner_type), |
| exp0)), |
| fold (build1 (REALPART_EXPR, |
| TREE_TYPE (inner_type), |
| exp1)))), |
| fold (build (EQ_EXPR, TREE_TYPE (exp), |
| fold (build1 (IMAGPART_EXPR, |
| TREE_TYPE (inner_type), |
| exp0)), |
| fold (build1 (IMAGPART_EXPR, |
| TREE_TYPE (inner_type), |
| exp1)))))), |
| if_false_label, if_true_label); |
| } |
| |
| else if (integer_zerop (TREE_OPERAND (exp, 1))) |
| do_jump (TREE_OPERAND (exp, 0), if_true_label, if_false_label); |
| |
| else if (GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_INT |
| && !can_compare_p (EQ, TYPE_MODE (inner_type), ccp_jump)) |
| do_jump_by_parts_equality (exp, if_false_label, if_true_label); |
| else |
| do_compare_and_jump (exp, EQ, EQ, if_false_label, if_true_label); |
| break; |
| } |
| |
| case NE_EXPR: |
| { |
| tree inner_type = TREE_TYPE (TREE_OPERAND (exp, 0)); |
| |
| if (GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_COMPLEX_FLOAT |
| || GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_COMPLEX_INT) |
| { |
| tree exp0 = save_expr (TREE_OPERAND (exp, 0)); |
| tree exp1 = save_expr (TREE_OPERAND (exp, 1)); |
| do_jump |
| (fold |
| (build (TRUTH_ORIF_EXPR, TREE_TYPE (exp), |
| fold (build (NE_EXPR, TREE_TYPE (exp), |
| fold (build1 (REALPART_EXPR, |
| TREE_TYPE (inner_type), |
| exp0)), |
| fold (build1 (REALPART_EXPR, |
| TREE_TYPE (inner_type), |
| exp1)))), |
| fold (build (NE_EXPR, TREE_TYPE (exp), |
| fold (build1 (IMAGPART_EXPR, |
| TREE_TYPE (inner_type), |
| exp0)), |
| fold (build1 (IMAGPART_EXPR, |
| TREE_TYPE (inner_type), |
| exp1)))))), |
| if_false_label, if_true_label); |
| } |
| |
| else if (integer_zerop (TREE_OPERAND (exp, 1))) |
| do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label); |
| |
| else if (GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_INT |
| && !can_compare_p (NE, TYPE_MODE (inner_type), ccp_jump)) |
| do_jump_by_parts_equality (exp, if_true_label, if_false_label); |
| else |
| do_compare_and_jump (exp, NE, NE, if_false_label, if_true_label); |
| break; |
| } |
| |
| case LT_EXPR: |
| mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))); |
| if (GET_MODE_CLASS (mode) == MODE_INT |
| && ! can_compare_p (LT, mode, ccp_jump)) |
| do_jump_by_parts_greater (exp, 1, if_false_label, if_true_label); |
| else |
| do_compare_and_jump (exp, LT, LTU, if_false_label, if_true_label); |
| break; |
| |
| case LE_EXPR: |
| mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))); |
| if (GET_MODE_CLASS (mode) == MODE_INT |
| && ! can_compare_p (LE, mode, ccp_jump)) |
| do_jump_by_parts_greater (exp, 0, if_true_label, if_false_label); |
| else |
| do_compare_and_jump (exp, LE, LEU, if_false_label, if_true_label); |
| break; |
| |
| case GT_EXPR: |
| mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))); |
| if (GET_MODE_CLASS (mode) == MODE_INT |
| && ! can_compare_p (GT, mode, ccp_jump)) |
| do_jump_by_parts_greater (exp, 0, if_false_label, if_true_label); |
| else |
| do_compare_and_jump (exp, GT, GTU, if_false_label, if_true_label); |
| break; |
| |
| case GE_EXPR: |
| mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))); |
| if (GET_MODE_CLASS (mode) == MODE_INT |
| && ! can_compare_p (GE, mode, ccp_jump)) |
| do_jump_by_parts_greater (exp, 1, if_true_label, if_false_label); |
| else |
| do_compare_and_jump (exp, GE, GEU, if_false_label, if_true_label); |
| break; |
| |
| case UNORDERED_EXPR: |
| case ORDERED_EXPR: |
| { |
| enum rtx_code cmp, rcmp; |
| int do_rev; |
| |
| if (code == UNORDERED_EXPR) |
| cmp = UNORDERED, rcmp = ORDERED; |
| else |
| cmp = ORDERED, rcmp = UNORDERED; |
| mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))); |
| |
| do_rev = 0; |
| if (! can_compare_p (cmp, mode, ccp_jump) |
| && (can_compare_p (rcmp, mode, ccp_jump) |
| /* If the target doesn't provide either UNORDERED or ORDERED |
| comparisons, canonicalize on UNORDERED for the library. */ |
| || rcmp == UNORDERED)) |
| do_rev = 1; |
| |
| if (! do_rev) |
| do_compare_and_jump (exp, cmp, cmp, if_false_label, if_true_label); |
| else |
| do_compare_and_jump (exp, rcmp, rcmp, if_true_label, if_false_label); |
| } |
| break; |
| |
| { |
| enum rtx_code rcode1; |
| enum tree_code tcode2; |
| |
| case UNLT_EXPR: |
| rcode1 = UNLT; |
| tcode2 = LT_EXPR; |
| goto unordered_bcc; |
| case UNLE_EXPR: |
| rcode1 = UNLE; |
| tcode2 = LE_EXPR; |
| goto unordered_bcc; |
| case UNGT_EXPR: |
| rcode1 = UNGT; |
| tcode2 = GT_EXPR; |
| goto unordered_bcc; |
| case UNGE_EXPR: |
| rcode1 = UNGE; |
| tcode2 = GE_EXPR; |
| goto unordered_bcc; |
| case UNEQ_EXPR: |
| rcode1 = UNEQ; |
| tcode2 = EQ_EXPR; |
| goto unordered_bcc; |
| |
| unordered_bcc: |
| mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))); |
| if (can_compare_p (rcode1, mode, ccp_jump)) |
| do_compare_and_jump (exp, rcode1, rcode1, if_false_label, |
| if_true_label); |
| else |
| { |
| tree op0 = save_expr (TREE_OPERAND (exp, 0)); |
| tree op1 = save_expr (TREE_OPERAND (exp, 1)); |
| tree cmp0, cmp1; |
| |
| /* If the target doesn't support combined unordered |
| compares, decompose into UNORDERED + comparison. */ |
| cmp0 = fold (build (UNORDERED_EXPR, TREE_TYPE (exp), op0, op1)); |
| cmp1 = fold (build (tcode2, TREE_TYPE (exp), op0, op1)); |
| exp = build (TRUTH_ORIF_EXPR, TREE_TYPE (exp), cmp0, cmp1); |
| do_jump (exp, if_false_label, if_true_label); |
| } |
| } |
| break; |
| |
| /* Special case: |
| __builtin_expect (<test>, 0) and |
| __builtin_expect (<test>, 1) |
| |
| We need to do this here, so that <test> is not converted to a SCC |
| operation on machines that use condition code registers and COMPARE |
| like the PowerPC, and then the jump is done based on whether the SCC |
| operation produced a 1 or 0. */ |
| case CALL_EXPR: |
| /* Check for a built-in function. */ |
| { |
| tree fndecl = get_callee_fndecl (exp); |
| tree arglist = TREE_OPERAND (exp, 1); |
| |
| if (fndecl |
| && DECL_BUILT_IN (fndecl) |
| && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_EXPECT |
| && arglist != NULL_TREE |
| && TREE_CHAIN (arglist) != NULL_TREE) |
| { |
| rtx seq = expand_builtin_expect_jump (exp, if_false_label, |
| if_true_label); |
| |
| if (seq != NULL_RTX) |
| { |
| emit_insn (seq); |
| return; |
| } |
| } |
| } |
| /* Fall through and generate the normal code. */ |
| |
| default: |
| normal: |
| temp = expand_expr (exp, NULL_RTX, VOIDmode, 0); |
| #if 0 |
| /* This is not needed any more and causes poor code since it causes |
| comparisons and tests from non-SI objects to have different code |
| sequences. */ |
| /* Copy to register to avoid generating bad insns by cse |
| from (set (mem ...) (arithop)) (set (cc0) (mem ...)). */ |
| if (!cse_not_expected && GET_CODE (temp) == MEM) |
| temp = copy_to_reg (temp); |
| #endif |
| do_pending_stack_adjust (); |
| /* Do any postincrements in the expression that was tested. */ |
| emit_queue (); |
| |
| if (GET_CODE (temp) == CONST_INT |
| || (GET_CODE (temp) == CONST_DOUBLE && GET_MODE (temp) == VOIDmode) |
| || GET_CODE (temp) == LABEL_REF) |
| { |
| rtx target = temp == const0_rtx ? if_false_label : if_true_label; |
| if (target) |
| emit_jump (target); |
| } |
| else if (GET_MODE_CLASS (GET_MODE (temp)) == MODE_INT |
| && ! can_compare_p (NE, GET_MODE (temp), ccp_jump)) |
| /* Note swapping the labels gives us not-equal. */ |
| do_jump_by_parts_equality_rtx (temp, if_true_label, if_false_label); |
| else if (GET_MODE (temp) != VOIDmode) |
| { |
| /* The RTL optimizers prefer comparisons against pseudos. */ |
| if (GET_CODE (temp) == SUBREG) |
| { |
| /* Compare promoted variables in their promoted mode. */ |
| if (SUBREG_PROMOTED_VAR_P (temp) |
| && GET_CODE (XEXP (temp, 0)) == REG) |
| temp = XEXP (temp, 0); |
| else |
| temp = copy_to_reg (temp); |
| } |
| do_compare_rtx_and_jump (temp, CONST0_RTX (GET_MODE (temp)), |
| NE, TREE_UNSIGNED (TREE_TYPE (exp)), |
| GET_MODE (temp), NULL_RTX, |
| if_false_label, if_true_label); |
| } |
| else |
| abort (); |
| } |
| |
| if (drop_through_label) |
| { |
| /* If do_jump produces code that might be jumped around, |
| do any stack adjusts from that code, before the place |
| where control merges in. */ |
| do_pending_stack_adjust (); |
| emit_label (drop_through_label); |
| } |
| } |
| |
| /* Given a comparison expression EXP for values too wide to be compared |
| with one insn, test the comparison and jump to the appropriate label. |
| The code of EXP is ignored; we always test GT if SWAP is 0, |
| and LT if SWAP is 1. */ |
| |
| static void |
| do_jump_by_parts_greater (tree exp, int swap, rtx if_false_label, |
| rtx if_true_label) |
| { |
| rtx op0 = expand_expr (TREE_OPERAND (exp, swap), NULL_RTX, VOIDmode, 0); |
| rtx op1 = expand_expr (TREE_OPERAND (exp, !swap), NULL_RTX, VOIDmode, 0); |
| enum machine_mode mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))); |
| int unsignedp = TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (exp, 0))); |
| |
| do_jump_by_parts_greater_rtx (mode, unsignedp, op0, op1, if_false_label, if_true_label); |
| } |
| |
| /* Compare OP0 with OP1, word at a time, in mode MODE. |
| UNSIGNEDP says to do unsigned comparison. |
| Jump to IF_TRUE_LABEL if OP0 is greater, IF_FALSE_LABEL otherwise. */ |
| |
| void |
| do_jump_by_parts_greater_rtx (enum machine_mode mode, int unsignedp, rtx op0, |
| rtx op1, rtx if_false_label, rtx if_true_label) |
| { |
| int nwords = (GET_MODE_SIZE (mode) / UNITS_PER_WORD); |
| rtx drop_through_label = 0; |
| int i; |
| |
| if (! if_true_label || ! if_false_label) |
| drop_through_label = gen_label_rtx (); |
| if (! if_true_label) |
| if_true_label = drop_through_label; |
| if (! if_false_label) |
| if_false_label = drop_through_label; |
| |
| /* Compare a word at a time, high order first. */ |
| for (i = 0; i < nwords; i++) |
| { |
| rtx op0_word, op1_word; |
| |
| if (WORDS_BIG_ENDIAN) |
| { |
| op0_word = operand_subword_force (op0, i, mode); |
| op1_word = operand_subword_force (op1, i, mode); |
| } |
| else |
| { |
| op0_word = operand_subword_force (op0, nwords - 1 - i, mode); |
| op1_word = operand_subword_force (op1, nwords - 1 - i, mode); |
| } |
| |
| /* All but high-order word must be compared as unsigned. */ |
| do_compare_rtx_and_jump (op0_word, op1_word, GT, |
| (unsignedp || i > 0), word_mode, NULL_RTX, |
| NULL_RTX, if_true_label); |
| |
| /* Consider lower words only if these are equal. */ |
| do_compare_rtx_and_jump (op0_word, op1_word, NE, unsignedp, word_mode, |
| NULL_RTX, NULL_RTX, if_false_label); |
| } |
| |
| if (if_false_label) |
| emit_jump (if_false_label); |
| if (drop_through_label) |
| emit_label (drop_through_label); |
| } |
| |
| /* Given an EQ_EXPR expression EXP for values too wide to be compared |
| with one insn, test the comparison and jump to the appropriate label. */ |
| |
| static void |
| do_jump_by_parts_equality (tree exp, rtx if_false_label, rtx if_true_label) |
| { |
| rtx op0 = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0); |
| rtx op1 = expand_expr (TREE_OPERAND (exp, 1), NULL_RTX, VOIDmode, 0); |
| enum machine_mode mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0))); |
| int nwords = (GET_MODE_SIZE (mode) / UNITS_PER_WORD); |
| int i; |
| rtx drop_through_label = 0; |
| |
| if (! if_false_label) |
| drop_through_label = if_false_label = gen_label_rtx (); |
| |
| for (i = 0; i < nwords; i++) |
| do_compare_rtx_and_jump (operand_subword_force (op0, i, mode), |
| operand_subword_force (op1, i, mode), |
| EQ, TREE_UNSIGNED (TREE_TYPE (exp)), |
| word_mode, NULL_RTX, if_false_label, NULL_RTX); |
| |
| if (if_true_label) |
| emit_jump (if_true_label); |
| if (drop_through_label) |
| emit_label (drop_through_label); |
| } |
| |
| /* Jump according to whether OP0 is 0. |
| We assume that OP0 has an integer mode that is too wide |
| for the available compare insns. */ |
| |
| void |
| do_jump_by_parts_equality_rtx (rtx op0, rtx if_false_label, rtx if_true_label) |
| { |
| int nwords = GET_MODE_SIZE (GET_MODE (op0)) / UNITS_PER_WORD; |
| rtx part; |
| int i; |
| rtx drop_through_label = 0; |
| |
| /* The fastest way of doing this comparison on almost any machine is to |
| "or" all the words and compare the result. If all have to be loaded |
| from memory and this is a very wide item, it's possible this may |
| be slower, but that's highly unlikely. */ |
| |
| part = gen_reg_rtx (word_mode); |
| emit_move_insn (part, operand_subword_force (op0, 0, GET_MODE (op0))); |
| for (i = 1; i < nwords && part != 0; i++) |
| part = expand_binop (word_mode, ior_optab, part, |
| operand_subword_force (op0, i, GET_MODE (op0)), |
| part, 1, OPTAB_WIDEN); |
| |
| if (part != 0) |
| { |
| do_compare_rtx_and_jump (part, const0_rtx, EQ, 1, word_mode, |
| NULL_RTX, if_false_label, if_true_label); |
| |
| return; |
| } |
| |
| /* If we couldn't do the "or" simply, do this with a series of compares. */ |
| if (! if_false_label) |
| drop_through_label = if_false_label = gen_label_rtx (); |
| |
| for (i = 0; i < nwords; i++) |
| do_compare_rtx_and_jump (operand_subword_force (op0, i, GET_MODE (op0)), |
| const0_rtx, EQ, 1, word_mode, NULL_RTX, |
| if_false_label, NULL_RTX); |
| |
| if (if_true_label) |
| emit_jump (if_true_label); |
| |
| if (drop_through_label) |
| emit_label (drop_through_label); |
| } |
| |
| /* Generate code for a comparison of OP0 and OP1 with rtx code CODE. |
| (including code to compute the values to be compared) |
| and set (CC0) according to the result. |
| The decision as to signed or unsigned comparison must be made by the caller. |
| |
| We force a stack adjustment unless there are currently |
| things pushed on the stack that aren't yet used. |
| |
| If MODE is BLKmode, SIZE is an RTX giving the size of the objects being |
| compared. */ |
| |
| rtx |
| compare_from_rtx (rtx op0, rtx op1, enum rtx_code code, int unsignedp, |
| enum machine_mode mode, rtx size) |
| { |
| enum rtx_code ucode; |
| rtx tem; |
| |
| /* If one operand is constant, make it the second one. Only do this |
| if the other operand is not constant as well. */ |
| |
| if (swap_commutative_operands_p (op0, op1)) |
| { |
| tem = op0; |
| op0 = op1; |
| op1 = tem; |
| code = swap_condition (code); |
| } |
| |
| if (flag_force_mem) |
| { |
| op0 = force_not_mem (op0); |
| op1 = force_not_mem (op1); |
| } |
| |
| do_pending_stack_adjust (); |
| |
| ucode = unsignedp ? unsigned_condition (code) : code; |
| if ((tem = simplify_relational_operation (ucode, mode, op0, op1)) != 0) |
| return tem; |
| |
| #if 0 |
| /* There's no need to do this now that combine.c can eliminate lots of |
| sign extensions. This can be less efficient in certain cases on other |
| machines. */ |
| |
| /* If this is a signed equality comparison, we can do it as an |
| unsigned comparison since zero-extension is cheaper than sign |
| extension and comparisons with zero are done as unsigned. This is |
| the case even on machines that can do fast sign extension, since |
| zero-extension is easier to combine with other operations than |
| sign-extension is. If we are comparing against a constant, we must |
| convert it to what it would look like unsigned. */ |
| if ((code == EQ || code == NE) && ! unsignedp |
| && GET_MODE_BITSIZE (GET_MODE (op0)) <= HOST_BITS_PER_WIDE_INT) |
| { |
| if (GET_CODE (op1) == CONST_INT |
| && (INTVAL (op1) & GET_MODE_MASK (GET_MODE (op0))) != INTVAL (op1)) |
| op1 = GEN_INT (INTVAL (op1) & GET_MODE_MASK (GET_MODE (op0))); |
| unsignedp = 1; |
| } |
| #endif |
| |
| emit_cmp_insn (op0, op1, code, size, mode, unsignedp); |
| |
| #if HAVE_cc0 |
| return gen_rtx_fmt_ee (code, VOIDmode, cc0_rtx, const0_rtx); |
| #else |
| return gen_rtx_fmt_ee (code, VOIDmode, op0, op1); |
| #endif |
| } |
| |
| /* Like do_compare_and_jump but expects the values to compare as two rtx's. |
| The decision as to signed or unsigned comparison must be made by the caller. |
| |
| If MODE is BLKmode, SIZE is an RTX giving the size of the objects being |
| compared. */ |
| |
| void |
| do_compare_rtx_and_jump (rtx op0, rtx op1, enum rtx_code code, int unsignedp, |
| enum machine_mode mode, rtx size, rtx if_false_label, |
| rtx if_true_label) |
| { |
| enum rtx_code ucode; |
| rtx tem; |
| int dummy_true_label = 0; |
| |
| /* Reverse the comparison if that is safe and we want to jump if it is |
| false. */ |
| if (! if_true_label && ! FLOAT_MODE_P (mode)) |
| { |
| if_true_label = if_false_label; |
| if_false_label = 0; |
| code = reverse_condition (code); |
| } |
| |
| /* If one operand is constant, make it the second one. Only do this |
| if the other operand is not constant as well. */ |
| |
| if (swap_commutative_operands_p (op0, op1)) |
| { |
| tem = op0; |
| op0 = op1; |
| op1 = tem; |
| code = swap_condition (code); |
| } |
| |
| if (flag_force_mem) |
| { |
| op0 = force_not_mem (op0); |
| op1 = force_not_mem (op1); |
| } |
| |
| do_pending_stack_adjust (); |
| |
| ucode = unsignedp ? unsigned_condition (code) : code; |
| if ((tem = simplify_relational_operation (ucode, mode, op0, op1)) != 0) |
| { |
| if (tem == const_true_rtx) |
| { |
| if (if_true_label) |
| emit_jump (if_true_label); |
| } |
| else |
| { |
| if (if_false_label) |
| emit_jump (if_false_label); |
| } |
| return; |
| } |
| |
| #if 0 |
| /* There's no need to do this now that combine.c can eliminate lots of |
| sign extensions. This can be less efficient in certain cases on other |
| machines. */ |
| |
| /* If this is a signed equality comparison, we can do it as an |
| unsigned comparison since zero-extension is cheaper than sign |
| extension and comparisons with zero are done as unsigned. This is |
| the case even on machines that can do fast sign extension, since |
| zero-extension is easier to combine with other operations than |
| sign-extension is. If we are comparing against a constant, we must |
| convert it to what it would look like unsigned. */ |
| if ((code == EQ || code == NE) && ! unsignedp |
| && GET_MODE_BITSIZE (GET_MODE (op0)) <= HOST_BITS_PER_WIDE_INT) |
| { |
| if (GET_CODE (op1) == CONST_INT |
| && (INTVAL (op1) & GET_MODE_MASK (GET_MODE (op0))) != INTVAL (op1)) |
| op1 = GEN_INT (INTVAL (op1) & GET_MODE_MASK (GET_MODE (op0))); |
| unsignedp = 1; |
| } |
| #endif |
| |
| if (! if_true_label) |
| { |
| dummy_true_label = 1; |
| if_true_label = gen_label_rtx (); |
| } |
| |
| emit_cmp_and_jump_insns (op0, op1, code, size, mode, unsignedp, |
| if_true_label); |
| |
| if (if_false_label) |
| emit_jump (if_false_label); |
| if (dummy_true_label) |
| emit_label (if_true_label); |
| } |
| |
| /* Generate code for a comparison expression EXP (including code to compute |
| the values to be compared) and a conditional jump to IF_FALSE_LABEL and/or |
| IF_TRUE_LABEL. One of the labels can be NULL_RTX, in which case the |
| generated code will drop through. |
| SIGNED_CODE should be the rtx operation for this comparison for |
| signed data; UNSIGNED_CODE, likewise for use if data is unsigned. |
| |
| We force a stack adjustment unless there are currently |
| things pushed on the stack that aren't yet used. */ |
| |
| static void |
| do_compare_and_jump (tree exp, enum rtx_code signed_code, |
| enum rtx_code unsigned_code, rtx if_false_label, |
| rtx if_true_label) |
| { |
| rtx op0, op1; |
| tree type; |
| enum machine_mode mode; |
| int unsignedp; |
| enum rtx_code code; |
| |
| /* Don't crash if the comparison was erroneous. */ |
| op0 = expand_expr (TREE_OPERAND (exp, 0), NULL_RTX, VOIDmode, 0); |
| if (TREE_CODE (TREE_OPERAND (exp, 0)) == ERROR_MARK) |
| return; |
| |
| op1 = expand_expr (TREE_OPERAND (exp, 1), NULL_RTX, VOIDmode, 0); |
| if (TREE_CODE (TREE_OPERAND (exp, 1)) == ERROR_MARK) |
| return; |
| |
| type = TREE_TYPE (TREE_OPERAND (exp, 0)); |
| mode = TYPE_MODE (type); |
| if (TREE_CODE (TREE_OPERAND (exp, 0)) == INTEGER_CST |
| && (TREE_CODE (TREE_OPERAND (exp, 1)) != INTEGER_CST |
| || (GET_MODE_BITSIZE (mode) |
| > GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, |
| 1))))))) |
| { |
| /* op0 might have been replaced by promoted constant, in which |
| case the type of second argument should be used. */ |
| type = TREE_TYPE (TREE_OPERAND (exp, 1)); |
| mode = TYPE_MODE (type); |
| } |
| unsignedp = TREE_UNSIGNED (type); |
| code = unsignedp ? unsigned_code : signed_code; |
| |
| #ifdef HAVE_canonicalize_funcptr_for_compare |
| /* If function pointers need to be "canonicalized" before they can |
| be reliably compared, then canonicalize them. */ |
| if (HAVE_canonicalize_funcptr_for_compare |
| && TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == POINTER_TYPE |
| && (TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0)))) |
| == FUNCTION_TYPE)) |
| { |
| rtx new_op0 = gen_reg_rtx (mode); |
| |
| emit_insn (gen_canonicalize_funcptr_for_compare (new_op0, op0)); |
| op0 = new_op0; |
| } |
| |
| if (HAVE_canonicalize_funcptr_for_compare |
| && TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 1))) == POINTER_TYPE |
| && (TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 1)))) |
| == FUNCTION_TYPE)) |
| { |
| rtx new_op1 = gen_reg_rtx (mode); |
| |
| emit_insn (gen_canonicalize_funcptr_for_compare (new_op1, op1)); |
| op1 = new_op1; |
| } |
| #endif |
| |
| /* Do any postincrements in the expression that was tested. */ |
| emit_queue (); |
| |
| do_compare_rtx_and_jump (op0, op1, code, unsignedp, mode, |
| ((mode == BLKmode) |
| ? expr_size (TREE_OPERAND (exp, 0)) : NULL_RTX), |
| if_false_label, if_true_label); |
| } |
