From 69eb2dc7a32de8cefa7a18d2e257c8ff59e782f5 Mon Sep 17 00:00:00 2001
From: Michael Beck <beck@ipd.info.uni-karlsruhe.de>
Date: Wed, 14 Nov 2007 14:41:08 +0000
Subject: [PATCH] - added more classification functions for floating point
 tarvals - speed up some functions - more comments added

[r16531]
---
 include/libfirm/tv.h | 20 ++++++++++++++++++++
 ir/tv/tv.c           | 40 +++++++++++++++++++++++++++++++++++-----
 2 files changed, 55 insertions(+), 5 deletions(-)

diff --git a/include/libfirm/tv.h b/include/libfirm/tv.h
index 0d7fe9007..a92175d20 100644
--- a/include/libfirm/tv.h
+++ b/include/libfirm/tv.h
@@ -615,4 +615,24 @@ unsigned tarval_ieee754_get_exact(void);
  */
 int tarval_enable_fp_ops(int enable);
 
+/**
+ * Check if its the a floating point NaN.
+ */
+int tarval_is_NaN(tarval *tv);
+
+/**
+ * Check if its the a floating point +inf.
+ */
+int tarval_is_plus_inf(tarval *tv);
+
+/**
+ * Check if its the a floating point -inf.
+ */
+int tarval_is_minus_inf(tarval *tv);
+
+/**
+ * Check if the tarval represents a finite value, ie neither NaN nor inf.
+ */
+int tarval_is_finite(tarval *tv);
+
 #endif  /* FIRM_TV_TV_H */
diff --git a/ir/tv/tv.c b/ir/tv/tv.c
index 1aa0deaea..b8858d9cf 100644
--- a/ir/tv/tv.c
+++ b/ir/tv/tv.c
@@ -237,10 +237,12 @@ static tarval *get_tarval_overflow(const void *value, int length, ir_mode *mode)
 
 	case irms_float_number:
 		if (SWITCH_NOINFINITY && fc_is_inf(value)) {
-			return fc_is_negative(value)?get_mode_min(mode):get_mode_max(mode);
+			/* clip infinity to maximum value */
+			return fc_is_negative(value) ? get_mode_min(mode) : get_mode_max(mode);
 		}
 
 		if (SWITCH_NODENORMALS && fc_is_subnormal(value)) {
+			/* clip denormals to zero */
 			return get_mode_null(mode);
 		}
 		break;
@@ -729,7 +731,7 @@ int tarval_is_negative(tarval *a) {
 			return sc_comp(a->value, get_mode_null(a->mode)->value) == -1 ? 1 : 0;
 
 	case irms_float_number:
-		return fc_comp(a->value, get_mode_null(a->mode)->value) == -1 ? 1 : 0;
+		return fc_is_negative(a->value);
 
 	default:
 		assert(0 && "not implemented");
@@ -743,7 +745,7 @@ int tarval_is_negative(tarval *a) {
 int tarval_is_null(tarval *a) {
 	return
 		a != tarval_bad &&
-		a == get_tarval_null(get_tarval_mode(a));
+		a == get_mode_null(get_tarval_mode(a));
 }
 
 /*
@@ -752,7 +754,7 @@ int tarval_is_null(tarval *a) {
 int tarval_is_one(tarval *a) {
 	return
 		a != tarval_bad &&
-		a == get_tarval_one(get_tarval_mode(a));
+		a == get_mode_one(get_tarval_mode(a));
 }
 
 int tarval_is_all_one(tarval *tv) {
@@ -767,7 +769,7 @@ int tarval_is_all_one(tarval *tv) {
 int tarval_is_minus_one(tarval *a) {
 	return
 		a != tarval_bad &&
-		a == get_tarval_minus_one(get_tarval_mode(a));
+		a == get_mode_minus_one(get_tarval_mode(a));
 }
 
 /*
@@ -1638,6 +1640,34 @@ unsigned tarval_ieee754_get_exact(void) {
 	return fc_is_exact();
 }
 
+/* check if its the a floating point NaN */
+int tarval_is_NaN(tarval *tv) {
+	if (! mode_is_float(tv->mode))
+		return 0;
+	return fc_is_nan(tv->value);
+}
+
+/* check if its the a floating point +inf */
+int tarval_is_plus_inf(tarval *tv) {
+	if (! mode_is_float(tv->mode))
+		return 0;
+	return fc_is_inf(tv->value) && !fc_is_negative(tv->value);
+}
+
+/* check if its the a floating point -inf */
+int tarval_is_minus_inf(tarval *tv) {
+	if (! mode_is_float(tv->mode))
+		return 0;
+	return fc_is_inf(tv->value) && fc_is_negative(tv->value);
+}
+
+/* check if the tarval represents a finite value */
+int tarval_is_finite(tarval *tv) {
+	if (mode_is_float(tv->mode))
+		return !fc_is_nan(tv->value) && !fc_is_inf(tv->value);
+	return 1;
+}
+
 /*
  * Sets the overflow mode for integer operations.
  */
-- 
2.20.1