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-rw-r--r--contrib/llvm-project/compiler-rt/lib/builtins/floatdixf.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/contrib/llvm-project/compiler-rt/lib/builtins/floatdixf.c b/contrib/llvm-project/compiler-rt/lib/builtins/floatdixf.c
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index 000000000000..3d9e664e4814
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+++ b/contrib/llvm-project/compiler-rt/lib/builtins/floatdixf.c
@@ -0,0 +1,41 @@
+//===-- floatdixf.c - Implement __floatdixf -------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements __floatdixf for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#if !_ARCH_PPC
+
+#include "int_lib.h"
+
+// Returns: convert a to a long double, rounding toward even.
+
+// Assumption: long double is a IEEE 80 bit floating point type padded to 128
+// bits di_int is a 64 bit integral type
+
+// gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee
+// eeee | 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm
+// mmmm mmmm mmmm
+
+COMPILER_RT_ABI xf_float __floatdixf(di_int a) {
+ if (a == 0)
+ return 0.0;
+ const unsigned N = sizeof(di_int) * CHAR_BIT;
+ const di_int s = a >> (N - 1);
+ a = (a ^ s) - s;
+ int clz = __builtin_clzll(a);
+ int e = (N - 1) - clz; // exponent
+ xf_bits fb;
+ fb.u.high.s.low = ((su_int)s & 0x00008000) | // sign
+ (e + 16383); // exponent
+ fb.u.low.all = a << clz; // mantissa
+ return fb.f;
+}
+
+#endif // !_ARCH_PPC