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authorAlexey Samsonov <samsonov@google.com>2014-02-14 09:20:33 +0000
committerAlexey Samsonov <samsonov@google.com>2014-02-14 09:20:33 +0000
commit53aa4fda49f94920139300227786ac47c393f1ce (patch)
tree6d022d04ee279fe1afd89668f346e28a9e3e1559 /lib/builtins/comparesf2.c
parent6d999e478fecb10dc43f20b85385d25cc239db0a (diff)
Move original compiler-rt functions (libgcc replacement) to lib/builtins directory
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@201393 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/builtins/comparesf2.c')
-rw-r--r--lib/builtins/comparesf2.c133
1 files changed, 133 insertions, 0 deletions
diff --git a/lib/builtins/comparesf2.c b/lib/builtins/comparesf2.c
new file mode 100644
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+++ b/lib/builtins/comparesf2.c
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+//===-- lib/comparesf2.c - Single-precision comparisons -----------*- C -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the following soft-fp_t comparison routines:
+//
+// __eqsf2 __gesf2 __unordsf2
+// __lesf2 __gtsf2
+// __ltsf2
+// __nesf2
+//
+// The semantics of the routines grouped in each column are identical, so there
+// is a single implementation for each, and wrappers to provide the other names.
+//
+// The main routines behave as follows:
+//
+// __lesf2(a,b) returns -1 if a < b
+// 0 if a == b
+// 1 if a > b
+// 1 if either a or b is NaN
+//
+// __gesf2(a,b) returns -1 if a < b
+// 0 if a == b
+// 1 if a > b
+// -1 if either a or b is NaN
+//
+// __unordsf2(a,b) returns 0 if both a and b are numbers
+// 1 if either a or b is NaN
+//
+// Note that __lesf2( ) and __gesf2( ) are identical except in their handling of
+// NaN values.
+//
+//===----------------------------------------------------------------------===//
+
+#define SINGLE_PRECISION
+#include "fp_lib.h"
+
+enum LE_RESULT {
+ LE_LESS = -1,
+ LE_EQUAL = 0,
+ LE_GREATER = 1,
+ LE_UNORDERED = 1
+};
+
+enum LE_RESULT __lesf2(fp_t a, fp_t b) {
+
+ const srep_t aInt = toRep(a);
+ const srep_t bInt = toRep(b);
+ const rep_t aAbs = aInt & absMask;
+ const rep_t bAbs = bInt & absMask;
+
+ // If either a or b is NaN, they are unordered.
+ if (aAbs > infRep || bAbs > infRep) return LE_UNORDERED;
+
+ // If a and b are both zeros, they are equal.
+ if ((aAbs | bAbs) == 0) return LE_EQUAL;
+
+ // If at least one of a and b is positive, we get the same result comparing
+ // a and b as signed integers as we would with a fp_ting-point compare.
+ if ((aInt & bInt) >= 0) {
+ if (aInt < bInt) return LE_LESS;
+ else if (aInt == bInt) return LE_EQUAL;
+ else return LE_GREATER;
+ }
+
+ // Otherwise, both are negative, so we need to flip the sense of the
+ // comparison to get the correct result. (This assumes a twos- or ones-
+ // complement integer representation; if integers are represented in a
+ // sign-magnitude representation, then this flip is incorrect).
+ else {
+ if (aInt > bInt) return LE_LESS;
+ else if (aInt == bInt) return LE_EQUAL;
+ else return LE_GREATER;
+ }
+}
+
+enum GE_RESULT {
+ GE_LESS = -1,
+ GE_EQUAL = 0,
+ GE_GREATER = 1,
+ GE_UNORDERED = -1 // Note: different from LE_UNORDERED
+};
+
+enum GE_RESULT __gesf2(fp_t a, fp_t b) {
+
+ const srep_t aInt = toRep(a);
+ const srep_t bInt = toRep(b);
+ const rep_t aAbs = aInt & absMask;
+ const rep_t bAbs = bInt & absMask;
+
+ if (aAbs > infRep || bAbs > infRep) return GE_UNORDERED;
+ if ((aAbs | bAbs) == 0) return GE_EQUAL;
+ if ((aInt & bInt) >= 0) {
+ if (aInt < bInt) return GE_LESS;
+ else if (aInt == bInt) return GE_EQUAL;
+ else return GE_GREATER;
+ } else {
+ if (aInt > bInt) return GE_LESS;
+ else if (aInt == bInt) return GE_EQUAL;
+ else return GE_GREATER;
+ }
+}
+
+ARM_EABI_FNALIAS(fcmpun, unordsf2)
+
+int __unordsf2(fp_t a, fp_t b) {
+ const rep_t aAbs = toRep(a) & absMask;
+ const rep_t bAbs = toRep(b) & absMask;
+ return aAbs > infRep || bAbs > infRep;
+}
+
+// The following are alternative names for the preceeding routines.
+
+enum LE_RESULT __eqsf2(fp_t a, fp_t b) {
+ return __lesf2(a, b);
+}
+
+enum LE_RESULT __ltsf2(fp_t a, fp_t b) {
+ return __lesf2(a, b);
+}
+
+enum LE_RESULT __nesf2(fp_t a, fp_t b) {
+ return __lesf2(a, b);
+}
+
+enum GE_RESULT __gtsf2(fp_t a, fp_t b) {
+ return __gesf2(a, b);
+}