src/compiler-rt/lib/builtins/arm/truncdfsf2vfp.S

   1 //===-- truncdfsf2vfp.S - Implement truncdfsf2vfp -------------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is dual licensed under the MIT and the University of Illinois Open
   6 // Source Licenses. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "../assembly.h"
  11
  12 //
  13 // extern float __truncdfsf2vfp(double a);
  14 //
  15 // Converts double precision float to signle precision result.
  16 // Uses Darwin calling convention where a double precision parameter is
  17 // passed in a R0/R1 pair and a signle precision result is returned in R0.
  18 //
  19         .syntax unified
  20         .p2align 2
  21 DEFINE_COMPILERRT_FUNCTION(__truncdfsf2vfp)
  22         vmov    d7, r0, r1   // load double from r0/r1 pair
  23         vcvt.f32.f64 s15, d7 // convert double to single (trucate precision)
  24         vmov    r0, s15      // return result in r0
  25         bx      lr
  26 END_COMPILERRT_FUNCTION(__truncdfsf2vfp)