diff options
Diffstat (limited to 'contrib/compiler-rt/lib/i386/floatdixf.S')
-rw-r--r-- | contrib/compiler-rt/lib/i386/floatdixf.S | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/contrib/compiler-rt/lib/i386/floatdixf.S b/contrib/compiler-rt/lib/i386/floatdixf.S new file mode 100644 index 0000000..f0271ab --- /dev/null +++ b/contrib/compiler-rt/lib/i386/floatdixf.S @@ -0,0 +1,29 @@ +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. + +#include "../assembly.h" + +// 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 +DEFINE_COMPILERRT_FUNCTION(__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__ |