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authorDaniel Dunbar <daniel@zuster.org>2009-07-01 06:04:03 +0000
committerDaniel Dunbar <daniel@zuster.org>2009-07-01 06:04:03 +0000
commit940515afdb99568d5d9cc9f6b9a80335a8e35646 (patch)
treeb1cb4700e147e652793f426981b157b1d19aef3c /lib/i386/floatdixf.S
parent72b5907f318972685252659ca191d63fbe2f352b (diff)
Fix a Darwinism, .s files meant to be preprocessed should be named .S.
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@74587 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/i386/floatdixf.S')
-rw-r--r--lib/i386/floatdixf.S28
1 files changed, 28 insertions, 0 deletions
diff --git a/lib/i386/floatdixf.S b/lib/i386/floatdixf.S
new file mode 100644
index 000000000..71e2d2abc
--- /dev/null
+++ b/lib/i386/floatdixf.S
@@ -0,0 +1,28 @@
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+
+// float __floatdixf(di_int a);
+
+#ifdef __i386__
+
+// This routine has some extra memory traffic, loading the 64-bit input via two
+// 32-bit loads, then immediately storing it back to the stack via a single 64-bit
+// store. This is to avoid a write-small, read-large stall.
+// However, if callers of this routine can be safely assumed to store the argument
+// via a 64-bt store, this is unnecessary memory traffic, and should be avoided.
+// It can be turned off by defining the TRUST_CALLERS_USE_64_BIT_STORES macro.
+
+.text
+.align 4
+.globl ___floatdixf
+___floatdixf:
+#ifndef TRUST_CALLERS_USE_64_BIT_STORES
+ movd 4(%esp), %xmm0
+ movd 8(%esp), %xmm1
+ punpckldq %xmm1, %xmm0
+ movq %xmm0, 4(%esp)
+#endif
+ fildll 4(%esp)
+ ret
+
+#endif // __i386__ \ No newline at end of file