From 10055ae2439dec264961a7a52131f8f1d40779af Mon Sep 17 00:00:00 2001 From: Brendan Kehoe Date: Fri, 8 Jan 1993 21:03:56 -0500 Subject: [PATCH] Cygnus<-->FSF merge. From-SVN: r3162 --- gcc/Makefile.in | 2 +- gcc/c-convert.c | 326 +----------------------------------------------- 2 files changed, 3 insertions(+), 325 deletions(-) diff --git a/gcc/Makefile.in b/gcc/Makefile.in index 75b5896fe08..b2181713219 100644 --- a/gcc/Makefile.in +++ b/gcc/Makefile.in @@ -369,7 +369,7 @@ OBJS = toplev.o version.o tree.o print-tree.o stor-layout.o fold-const.o \ regclass.o local-alloc.o global.o reload.o reload1.o caller-save.o \ insn-peep.o reorg.o sched.o final.o recog.o reg-stack.o \ insn-recog.o insn-extract.o insn-output.o insn-emit.o \ - insn-attrtab.o aux-output.o getpwd.o $(EXTRA_OBJS) + insn-attrtab.o aux-output.o getpwd.o convert.o $(EXTRA_OBJS) # GEN files are listed separately, so they can be built before doing parallel # makes for cc1 or cc1plus. Otherwise sequent parallel make attempts to load diff --git a/gcc/c-convert.c b/gcc/c-convert.c index 8b90f273fac..55264732b9a 100644 --- a/gcc/c-convert.c +++ b/gcc/c-convert.c @@ -26,6 +26,7 @@ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "config.h" #include "tree.h" #include "flags.h" +#include "convert.h" /* Change of width--truncation and extension of integers or reals-- is represented with NOP_EXPR. Proper functioning of many things @@ -37,7 +38,7 @@ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ Here is a list of all the functions that assume that widening and narrowing is always done with a NOP_EXPR: - In c-convert.c, convert_to_integer. + In convert.c, convert_to_integer. In c-typeck.c, build_binary_op (boolean ops), and truthvalue_conversion. In expr.c: expand_expr, for operands of a MULT_EXPR. In fold-const.c: fold. @@ -45,330 +46,7 @@ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ /* Subroutines of `convert'. */ -static tree -convert_to_pointer (type, expr) - tree type, expr; -{ - register tree intype = TREE_TYPE (expr); - register enum tree_code form = TREE_CODE (intype); - - if (integer_zerop (expr)) - { - if (type == TREE_TYPE (null_pointer_node)) - return null_pointer_node; - expr = build_int_2 (0, 0); - TREE_TYPE (expr) = type; - return expr; - } - - if (form == POINTER_TYPE) - return build1 (NOP_EXPR, type, expr); - - - if (form == INTEGER_TYPE || form == ENUMERAL_TYPE) - { - if (type_precision (intype) == POINTER_SIZE) - return build1 (CONVERT_EXPR, type, expr); - expr = convert (type_for_size (POINTER_SIZE, 0), expr); - if (TYPE_MODE (TREE_TYPE (expr)) != TYPE_MODE (type)) - /* There is supposed to be some integral type - that is the same width as a pointer. */ - abort (); - return convert_to_pointer (type, expr); - } - - error ("cannot convert to a pointer type"); - - return null_pointer_node; -} - -static tree -convert_to_real (type, expr) - tree type, expr; -{ - register enum tree_code form = TREE_CODE (TREE_TYPE (expr)); - - if (form == REAL_TYPE) - return build1 (flag_float_store ? CONVERT_EXPR : NOP_EXPR, - type, expr); - - if (form == INTEGER_TYPE || form == ENUMERAL_TYPE) - return build1 (FLOAT_EXPR, type, expr); - - if (form == POINTER_TYPE) - error ("pointer value used where a float was expected"); - else - error ("aggregate value used where a float was expected"); - - { - register tree tem = make_node (REAL_CST); - TREE_TYPE (tem) = type; - TREE_REAL_CST (tem) = REAL_VALUE_ATOF ("0.0"); - return tem; - } -} - -/* The result of this is always supposed to be a newly created tree node - not in use in any existing structure. */ - -static tree -convert_to_integer (type, expr) - tree type, expr; -{ - register tree intype = TREE_TYPE (expr); - register enum tree_code form = TREE_CODE (intype); - - if (form == POINTER_TYPE) - { - if (integer_zerop (expr)) - expr = integer_zero_node; - else - expr = fold (build1 (CONVERT_EXPR, - type_for_size (POINTER_SIZE, 0), expr)); - intype = TREE_TYPE (expr); - form = TREE_CODE (intype); - if (intype == type) - return expr; - } - if (form == INTEGER_TYPE || form == ENUMERAL_TYPE) - { - register unsigned outprec = TYPE_PRECISION (type); - register unsigned inprec = TYPE_PRECISION (intype); - register enum tree_code ex_form = TREE_CODE (expr); - - /* If we are widening the type, put in an explicit conversion. - Similarly if we are not changing the width. However, if this is - a logical operation that just returns 0 or 1, we can change the - type of the expression (see below). */ - - if (TREE_CODE_CLASS (ex_form) == '<' - || ex_form == TRUTH_AND_EXPR || ex_form == TRUTH_ANDIF_EXPR - || ex_form == TRUTH_OR_EXPR || ex_form == TRUTH_ORIF_EXPR - || ex_form == TRUTH_XOR_EXPR || ex_form == TRUTH_NOT_EXPR) - { - TREE_TYPE (expr) = type; - return expr; - } - else if (outprec >= inprec) - return build1 (NOP_EXPR, type, expr); - -/* Here detect when we can distribute the truncation down past some arithmetic. - For example, if adding two longs and converting to an int, - we can equally well convert both to ints and then add. - For the operations handled here, such truncation distribution - is always safe. - It is desirable in these cases: - 1) when truncating down to full-word from a larger size - 2) when truncating takes no work. - 3) when at least one operand of the arithmetic has been extended - (as by C's default conversions). In this case we need two conversions - if we do the arithmetic as already requested, so we might as well - truncate both and then combine. Perhaps that way we need only one. - - Note that in general we cannot do the arithmetic in a type - shorter than the desired result of conversion, even if the operands - are both extended from a shorter type, because they might overflow - if combined in that type. The exceptions to this--the times when - two narrow values can be combined in their narrow type even to - make a wider result--are handled by "shorten" in build_binary_op. */ - - switch (ex_form) - { - case RSHIFT_EXPR: - /* We can pass truncation down through right shifting - when the shift count is a nonpositive constant. */ - if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST - && tree_int_cst_lt (TREE_OPERAND (expr, 1), integer_one_node)) - goto trunc1; - break; - - case LSHIFT_EXPR: - /* We can pass truncation down through left shifting - when the shift count is a nonnegative constant. */ - if (TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST - && ! tree_int_cst_lt (TREE_OPERAND (expr, 1), integer_zero_node) - && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST) - { - /* If shift count is less than the width of the truncated type, - really shift. */ - if (tree_int_cst_lt (TREE_OPERAND (expr, 1), TYPE_SIZE (type))) - /* In this case, shifting is like multiplication. */ - goto trunc1; - else - /* If it is >= that width, result is zero. - Handling this with trunc1 would give the wrong result: - (int) ((long long) a << 32) is well defined (as 0) - but (int) a << 32 is undefined and would get a warning. */ - return convert_to_integer (type, integer_zero_node); - } - break; - - case MAX_EXPR: - case MIN_EXPR: - case MULT_EXPR: - { - tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type); - tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type); - - /* Don't distribute unless the output precision is at least as big - as the actual inputs. Otherwise, the comparison of the - truncated values will be wrong. */ - if (outprec >= TYPE_PRECISION (TREE_TYPE (arg0)) - && outprec >= TYPE_PRECISION (TREE_TYPE (arg1)) - /* If signedness of arg0 and arg1 don't match, - we can't necessarily find a type to compare them in. */ - && (TREE_UNSIGNED (TREE_TYPE (arg0)) - == TREE_UNSIGNED (TREE_TYPE (arg1)))) - goto trunc1; - break; - } - - case PLUS_EXPR: - case MINUS_EXPR: - case BIT_AND_EXPR: - case BIT_IOR_EXPR: - case BIT_XOR_EXPR: - case BIT_ANDTC_EXPR: - trunc1: - { - tree arg0 = get_unwidened (TREE_OPERAND (expr, 0), type); - tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type); - - if (outprec >= BITS_PER_WORD - || TRULY_NOOP_TRUNCATION (outprec, inprec) - || inprec > TYPE_PRECISION (TREE_TYPE (arg0)) - || inprec > TYPE_PRECISION (TREE_TYPE (arg1))) - { - /* Do the arithmetic in type TYPEX, - then convert result to TYPE. */ - register tree typex = type; - - /* Can't do arithmetic in enumeral types - so use an integer type that will hold the values. */ - if (TREE_CODE (typex) == ENUMERAL_TYPE) - typex = type_for_size (TYPE_PRECISION (typex), - TREE_UNSIGNED (typex)); - - /* But now perhaps TYPEX is as wide as INPREC. - In that case, do nothing special here. - (Otherwise would recurse infinitely in convert. */ - if (TYPE_PRECISION (typex) != inprec) - { - /* Don't do unsigned arithmetic where signed was wanted, - or vice versa. - Exception: if either of the original operands were - unsigned then can safely do the work as unsigned. - And we may need to do it as unsigned - if we truncate to the original size. */ - typex = ((TREE_UNSIGNED (TREE_TYPE (expr)) - || TREE_UNSIGNED (TREE_TYPE (arg0)) - || TREE_UNSIGNED (TREE_TYPE (arg1))) - ? unsigned_type (typex) : signed_type (typex)); - return convert (type, - build_binary_op (ex_form, - convert (typex, arg0), - convert (typex, arg1), - 0)); - } - } - } - break; - - case NEGATE_EXPR: - case BIT_NOT_EXPR: - { - register tree typex = type; - - /* Can't do arithmetic in enumeral types - so use an integer type that will hold the values. */ - if (TREE_CODE (typex) == ENUMERAL_TYPE) - typex = type_for_size (TYPE_PRECISION (typex), - TREE_UNSIGNED (typex)); - - /* But now perhaps TYPEX is as wide as INPREC. - In that case, do nothing special here. - (Otherwise would recurse infinitely in convert. */ - if (TYPE_PRECISION (typex) != inprec) - { - /* Don't do unsigned arithmetic where signed was wanted, - or vice versa. */ - typex = (TREE_UNSIGNED (TREE_TYPE (expr)) - ? unsigned_type (typex) : signed_type (typex)); - return convert (type, - build_unary_op (ex_form, - convert (typex, TREE_OPERAND (expr, 0)), - 1)); - } - } - - case NOP_EXPR: - /* If truncating after truncating, might as well do all at once. - If truncating after extending, we may get rid of wasted work. */ - return convert (type, get_unwidened (TREE_OPERAND (expr, 0), type)); - - case COND_EXPR: - /* Can treat the two alternative values like the operands - of an arithmetic expression. */ - { - tree arg1 = get_unwidened (TREE_OPERAND (expr, 1), type); - tree arg2 = get_unwidened (TREE_OPERAND (expr, 2), type); - - if (outprec >= BITS_PER_WORD - || TRULY_NOOP_TRUNCATION (outprec, inprec) - || inprec > TYPE_PRECISION (TREE_TYPE (arg1)) - || inprec > TYPE_PRECISION (TREE_TYPE (arg2))) - { - /* Do the arithmetic in type TYPEX, - then convert result to TYPE. */ - register tree typex = type; - - /* Can't do arithmetic in enumeral types - so use an integer type that will hold the values. */ - if (TREE_CODE (typex) == ENUMERAL_TYPE) - typex = type_for_size (TYPE_PRECISION (typex), - TREE_UNSIGNED (typex)); - - /* But now perhaps TYPEX is as wide as INPREC. - In that case, do nothing special here. - (Otherwise would recurse infinitely in convert. */ - if (TYPE_PRECISION (typex) != inprec) - { - /* Don't do unsigned arithmetic where signed was wanted, - or vice versa. */ - typex = (TREE_UNSIGNED (TREE_TYPE (expr)) - ? unsigned_type (typex) : signed_type (typex)); - return convert (type, - fold (build (COND_EXPR, typex, - TREE_OPERAND (expr, 0), - convert (typex, arg1), - convert (typex, arg2)))); - } - else - /* It is sometimes worthwhile - to push the narrowing down through the conditional. */ - return fold (build (COND_EXPR, type, - TREE_OPERAND (expr, 0), - convert (type, TREE_OPERAND (expr, 1)), - convert (type, TREE_OPERAND (expr, 2)))); - } - } - } - - return build1 (NOP_EXPR, type, expr); - } - - if (form == REAL_TYPE) - return build1 (FIX_TRUNC_EXPR, type, expr); - - error ("aggregate value used where an integer was expected"); - - { - register tree tem = build_int_2 (0, 0); - TREE_TYPE (tem) = type; - return tem; - } -} /* Create an expression whose value is that of EXPR, converted to type TYPE. The TREE_TYPE of the value -- 2.30.2