From 9b3388bea495d027aa618118096a8223f6866437 Mon Sep 17 00:00:00 2001
From: xleroy <xleroy@fca1b0fc-160b-0410-b1d3-a4f43f01ea2e>
Date: Mon, 6 May 2013 08:20:06 +0000
Subject: Support for in64 -> float conversions w/ correct rounding.

git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2235 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e
---
 runtime/powerpc/i64_stof.s | 68 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)
 create mode 100644 runtime/powerpc/i64_stof.s

(limited to 'runtime/powerpc/i64_stof.s')

diff --git a/runtime/powerpc/i64_stof.s b/runtime/powerpc/i64_stof.s
new file mode 100644
index 00000000..05b36a78
--- /dev/null
+++ b/runtime/powerpc/i64_stof.s
@@ -0,0 +1,68 @@
+# *****************************************************************
+#
+#               The Compcert verified compiler
+#
+#           Xavier Leroy, INRIA Paris-Rocquencourt
+#
+# Copyright (c) 2013 Institut National de Recherche en Informatique et
+#  en Automatique.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+#     * Neither the name of the <organization> nor the
+#       names of its contributors may be used to endorse or promote products
+#       derived from this software without specific prior written permission.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT
+# HOLDER> BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+# EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+# PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+# LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+# NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# *********************************************************************
+
+# Helper functions for 64-bit integer arithmetic.  PowerPC version.
+
+        .text
+
+### Conversion from signed long to single float	
+
+        .balign 16
+        .globl __i64_stof
+__i64_stof:
+	mflr r9
+   # Check whether -2^53 <= X < 2^53	
+        srawi r5, r3, 31
+        srawi r6, r3, 21        # (r5,r6) = X >> 53
+        addic r6, r6, 1
+        addze r5, r5            # (r5,r6) = (X >> 53) + 1
+        cmplwi r5, 2
+        blt 1f
+   # X is large enough that double rounding can occur.
+   # Avoid it by nudging X away from the points where double rounding
+   # occurs (the "round to odd" technique)
+        rlwinm r0, r4, 0, 21, 31 # extract bits 0 to 11 of X
+        addi r0, r0, 0x7FF      # r0 = (X & 0x7FF) + 0x7FF
+   # bit 12 of r0 is 0 if all low 12 bits of X are 0, 1 otherwise
+   # bits 13-31 of r0 are 0
+        or r4, r4, r0           # correct bit number 12 of X
+        rlwinm r4, r4, 0, 0, 20 # set to 0 bits 0 to 11 of X
+   # Convert to double, then round to single	
+1:      bl __i64_stod
+        mtlr r9
+        frsp f1, f1
+        blr
+        .type __i64_stof, @function
+        .size __i64_stof, .-__i64_stof
+	
-- 
cgit