| Message ID | 1478878946-22725-2-git-send-email-james.greenhalgh@arm.com |
|---|---|
| State | New |
| Headers | show |
On 11/11/16 15:42, James Greenhalgh wrote: > Hi, > > Conversions from double precision floats to the ARM __fp16 are required > to round only once. > > This patch adds a functions named __gnu_d2h_ieee and > __gnu_d2h_alternative for double to __fp16 conversions in IEEE and ARM > alternative format. The make use of the existing __gnu_float2h_internal > conversion function which rounds once only. > > Bootstrapped on an ARMv8-A machine with no issues, and cross-tested with > a range of multilibs. > > OK? Ok. Thanks, Kyrill > Thanks, > James > --- > > libgcc/ > > 2016-11-09 James Greenhalgh <james.greenhalgh@arm.com> > Matthew Wahab <matthew.wahab@arm.com> > > * config/arm/fp16.c (binary64): New. > (__gnu_d2h_internal): New. > (__gnu_d2h_ieee): New. > (__gnu_d2h_alternative): New. >
diff --git a/libgcc/config/arm/fp16.c b/libgcc/config/arm/fp16.c index ba89796..a656988 100644 --- a/libgcc/config/arm/fp16.c +++ b/libgcc/config/arm/fp16.c @@ -43,6 +43,15 @@ binary32 = 23 /* significand. */ }; +static const struct format +binary64 = +{ + 64, /* size. */ + 1023, /* bias. */ + 11, /* exponent. */ + 52 /* significand. */ +}; + static inline unsigned short __gnu_float2h_internal (const struct format* fmt, unsigned long long a, int ieee) @@ -136,6 +145,12 @@ __gnu_f2h_internal (unsigned int a, int ieee) return __gnu_float2h_internal (&binary32, (unsigned long long) a, ieee); } +static inline unsigned short +__gnu_d2h_internal (unsigned long long a, int ieee) +{ + return __gnu_float2h_internal (&binary64, a, ieee); +} + unsigned int __gnu_h2f_internal(unsigned short a, int ieee) { @@ -184,3 +199,15 @@ __gnu_h2f_alternative(unsigned short a) { return __gnu_h2f_internal(a, 0); } + +unsigned short +__gnu_d2h_ieee (unsigned long long a) +{ + return __gnu_d2h_internal (a, 1); +} + +unsigned short +__gnu_d2h_alternative (unsigned long long x) +{ + return __gnu_d2h_internal (x, 0); +}