Add support for float->int conversion (no overflow handling yet)

[r15709]

ir/tv/fltcalc.c

@@ -1636,6 +1636,61 @@ fp_value *fc_rnd(const fp_value *a, fp_value *result) {
 	return result;
 }
 
+/*
+ * convert a floating point value into an sc value ...
+ */
+int fc_flt2int(const fp_value *a, void *result, ir_mode *dst_mode) {
+	if (a->desc.clss == NORMAL) {
+		int exp_bias = (1 << (a->desc.exponent_size - 1)) - 1;
+		int exp_val  = sc_val_to_long(_exp(a)) - exp_bias;
+		int shift, highest;
+
+		if (a->sign && !mode_is_signed(dst_mode)) {
+			/* FIXME: for now we cannot convert this */
+			return 0;
+		}
+
+		assert(exp_val >= 0 && "floating point value not integral before fc_flt2int() call");
+		shift = a->desc.mantissa_size - exp_val + 2;
+
+		sc_shrI(_mant(a), shift, 64, 0, result);
+
+		/* check for overflow */
+		highest = sc_get_highest_set_bit(result);
+
+		if (mode_is_signed(dst_mode)) {
+			if (highest == sc_get_lowest_set_bit(result)) {
+				/* need extra test for MIN_INT */
+				if (highest >= get_mode_size_bits(dst_mode)) {
+					/* FIXME: handle overflow */
+					return 0;
+				}
+			} else {
+				if (highest >= get_mode_size_bits(dst_mode) - 1) {
+					/* FIXME: handle overflow */
+					return 0;
+				}
+			}
+		} else {
+			if (highest >= get_mode_size_bits(dst_mode)) {
+				/* FIXME: handle overflow */
+				return 0;
+			}
+		}
+
+		if (a->sign)
+			sc_neg(result, result);
+
+		return 1;
+	}
+	else if (a->desc.clss == ZERO) {
+		sc_zero(result);
+		return 1;
+	}
+	return 0;
+}
+
+
 unsigned fc_set_immediate_precision(unsigned bits) {
 	unsigned old = immediate_prec;
 

ir/tv/fltcalc.h

@@ -28,6 +28,7 @@
 #define FIRM_TV_FLTCALC_H
 
 #include "firm_config.h"
+#include "firm_types.h"
 
 #ifdef HAVE_LONG_DOUBLE
 /* XXX Set this via autoconf */
@@ -170,6 +171,11 @@ char *fc_print(const fp_value *a, char *buf, int buflen, unsigned base);
  */
 int fc_comp(const fp_value *a, const fp_value *b);
 
+/**
+ * Converts an floating point value into an integer value.
+ */
+int fc_flt2int(const fp_value *a, void *result, ir_mode *dst_mode);
+
 /**
  * Returns non-zero if the mantissa is zero, i.e. 1.0Exxx
  */

ir/tv/strcalc.c

@@ -1503,7 +1503,6 @@ void sc_sub(const void *value1, const void *value2, void *buffer) {
 }
 
 void sc_neg(const void *value1, void *buffer) {
-	CLEAR_BUFFER(calc_buffer);
 	carry_flag = 0;
 
 	DEBUGPRINTF_COMPUTATION(("- %s ->", sc_print_hex(value1)));
@@ -1662,9 +1661,7 @@ void sc_shl(const void *val1, const void *val2, int radius, int sign, void *buff
 	}
 }
 
-void sc_shr(const void *val1, const void *val2, int radius, int sign, void *buffer) {
-	long offset = sc_val_to_long(val2);
-
+void sc_shrI(const void *val1, long offset, int radius, int sign, void *buffer) {
 	carry_flag = 0;
 
 	DEBUGPRINTF_COMPUTATION(("%s >>u %ld ", sc_print_hex(value1), offset));
@@ -1677,6 +1674,12 @@ void sc_shr(const void *val1, const void *val2, int radius, int sign, void *buff
 	}
 }
 
+void sc_shr(const void *val1, const void *val2, int radius, int sign, void *buffer) {
+	long offset = sc_val_to_long(val2);
+
+	sc_shrI(val1, offset, radius, sign, buffer);
+}
+
 void sc_shrs(const void *val1, const void *val2, int radius, int sign, void *buffer) {
 	long offset = sc_val_to_long(val2);
 
@@ -1706,3 +1709,10 @@ void sc_rot(const void *val1, const void *val2, int radius, int sign, void *buff
 		memmove(buffer, calc_buffer, calc_buffer_size);
 	}
 }
+
+void sc_zero(void *buffer) {
+	if (buffer == NULL)
+		buffer = calc_buffer;
+	CLEAR_BUFFER(buffer);
+	carry_flag = 0;
+}

ir/tv/strcalc.h

@@ -148,6 +148,11 @@ void sc_divmod(const void *value1, const void *value2, void *div_buffer, void *m
  */
 void sc_shl(const void *value1, const void *value2, int radius, int sign, void *buffer);
 
+/**
+ * buffer = value1 >>u offset
+ */
+void sc_shrI(const void *val1, long offset, int radius, int sign, void *buffer);
+
 /**
  * buffer = value1 >>u value2
  */
@@ -163,6 +168,11 @@ void sc_shrs(const void *value1, const void *value2, int radius, int sign, void
  */
 void sc_rot(const void *value1, const void *value2, int radius, int sign, void *buffer);
 
+/**
+ * buffer = 0
+ */
+void sc_zero(void *buffer);
+
 /*
  * function declarations
  */

ir/tv/tv.c

@@ -782,13 +782,14 @@ pn_Cmp tarval_cmp(tarval *a, tarval *b) {
 /*
  * convert to other mode
  */
-tarval *tarval_convert_to(tarval *src, ir_mode *m) {
+tarval *tarval_convert_to(tarval *src, ir_mode *dst_mode) {
 	char *buffer;
+	fp_value *res;
 
 	assert(src);
-	assert(m);
+	assert(dst_mode);
 
-	if (src->mode == m) return src;
+	if (src->mode == dst_mode) return src;
 
 	if (get_mode_n_vector_elems(src->mode) > 1) {
 		/* vector arithmetic not implemented yet */
@@ -803,9 +804,9 @@ tarval *tarval_convert_to(tarval *src, ir_mode *m) {
 
 		/* cast float to something */
 	case irms_float_number:
-		switch (get_mode_sort(m)) {
+		switch (get_mode_sort(dst_mode)) {
 		case irms_float_number:
-			switch (get_mode_size_bits(m)) {
+			switch (get_mode_size_bits(dst_mode)) {
 			case 32:
 				fc_cast(src->value, 8, 23, NULL);
 				break;
@@ -818,25 +819,23 @@ tarval *tarval_convert_to(tarval *src, ir_mode *m) {
 			default:
 				break;
 			}
-			return get_tarval(fc_get_buffer(), fc_get_buffer_length(), m);
+			return get_tarval(fc_get_buffer(), fc_get_buffer_length(), dst_mode);
 
 		case irms_int_number:
 			switch (GET_FLOAT_TO_INT_MODE()) {
 			case TRUNCATE:
-				fc_int(src->value, NULL);
+				res = fc_int(src->value, NULL);
 				break;
 			case ROUND:
-				fc_rnd(src->value, NULL);
+				res = fc_rnd(src->value, NULL);
 				break;
 			default:
 				assert(0);
 				break;
 			}
-			/* FIXME: floating point unit can't produce a value in integer
-			 * representation
-			 * an intermediate representation is needed here first. */
-			/*  return get_tarval(); */
-			return tarval_bad;
+			if (! fc_flt2int(res, sc_get_buffer(), dst_mode))
+				return tarval_bad;
+			return get_tarval(sc_get_buffer(), sc_get_buffer_length(), dst_mode);
 
 		default:
 			/* the rest can't be converted */
@@ -846,14 +845,14 @@ tarval *tarval_convert_to(tarval *src, ir_mode *m) {
 
 	/* cast int/characters to something */
 	case irms_int_number:
-		switch (get_mode_sort(m)) {
+		switch (get_mode_sort(dst_mode)) {
 
 		case irms_reference:
 		case irms_int_number:
 			buffer = alloca(sc_get_buffer_length());
 			memcpy(buffer, src->value, sc_get_buffer_length());
-			sign_extend(buffer, m);
-			return get_tarval_overflow(buffer, src->length, m);
+			sign_extend(buffer, dst_mode);
+			return get_tarval_overflow(buffer, src->length, dst_mode);
 
 		case irms_internal_boolean:
 			/* XXX C semantics */
@@ -870,7 +869,7 @@ tarval *tarval_convert_to(tarval *src, ir_mode *m) {
 			snprintf(buffer, 100, "%s",
 				sc_print(src->value, get_mode_size_bits(src->mode), SC_DEC, mode_is_signed(src->mode)));
 			buffer[100 - 1] = '\0';
-			switch (get_mode_size_bits(m)) {
+			switch (get_mode_size_bits(dst_mode)) {
 			case 32:
 				fc_val_from_str(buffer, 0, 8, 23, NULL);
 				break;
@@ -881,7 +880,7 @@ tarval *tarval_convert_to(tarval *src, ir_mode *m) {
 				fc_val_from_str(buffer, 0, 15, 64, NULL);
 				break;
 			}
-			return get_tarval(fc_get_buffer(), fc_get_buffer_length(), m);
+			return get_tarval(fc_get_buffer(), fc_get_buffer_length(), dst_mode);
 
 		default:
 			break;
@@ -890,16 +889,16 @@ tarval *tarval_convert_to(tarval *src, ir_mode *m) {
 
 	case irms_internal_boolean:
 		/* beware: this is C semantic for the INTERNAL boolean mode */
-		if (get_mode_sort(m) == irms_int_number)
-			return src == tarval_b_true ? get_mode_one(m) : get_mode_null(m);
+		if (get_mode_sort(dst_mode) == irms_int_number)
+			return src == tarval_b_true ? get_mode_one(dst_mode) : get_mode_null(dst_mode);
 		break;
 
 	case irms_reference:
-		if (get_mode_sort(m) == irms_int_number) {
+		if (get_mode_sort(dst_mode) == irms_int_number) {
 			buffer = alloca(sc_get_buffer_length());
 			memcpy(buffer, src->value, sc_get_buffer_length());
 			sign_extend(buffer, src->mode);
-			return get_tarval_overflow(buffer, src->length, m);
+			return get_tarval_overflow(buffer, src->length, dst_mode);
 		}
 		break;
 	}