[Libclc-dev] [PATCH v2 1/1] Implement generic mad_sat
Jan Vesely
jan.vesely at rutgers.edu
Tue Aug 5 15:32:04 PDT 2014
On Tue, 2014-08-05 at 14:51 -0500, Aaron Watry wrote:
> On Tue, Aug 5, 2014 at 10:06 AM, Jan Vesely <jan.vesely at rutgers.edu> wrote:
> > v2: Fix trailing whitespace
> > Fix signed long overflow
> > improve comment
> >
> > Signed-off-by: Jan Vesely <jan.vesely at rutgers.edu>
> > ---
> >
> > NOTE: Use http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20140804/229312.html to avoid llvm segfault
> >
> > generic/include/clc/clc.h | 1 +
> > generic/include/clc/integer/mad_sat.h | 3 ++
> > generic/include/clc/integer/mad_sat.inc | 1 +
> > generic/lib/SOURCES | 1 +
> > generic/lib/clcmacro.h | 22 ++++++++++
> > generic/lib/integer/mad_sat.cl | 72 +++++++++++++++++++++++++++++++++
> > 6 files changed, 100 insertions(+)
> > create mode 100644 generic/include/clc/integer/mad_sat.h
> > create mode 100644 generic/include/clc/integer/mad_sat.inc
> > create mode 100644 generic/lib/integer/mad_sat.cl
> >
> > diff --git a/generic/include/clc/clc.h b/generic/include/clc/clc.h
> > index 9815c56..aca9b53 100644
> > --- a/generic/include/clc/clc.h
> > +++ b/generic/include/clc/clc.h
> > @@ -82,6 +82,7 @@
> > #include <clc/integer/hadd.h>
> > #include <clc/integer/mad24.h>
> > #include <clc/integer/mad_hi.h>
> > +#include <clc/integer/mad_sat.h>
> > #include <clc/integer/mul24.h>
> > #include <clc/integer/mul_hi.h>
> > #include <clc/integer/rhadd.h>
> > diff --git a/generic/include/clc/integer/mad_sat.h b/generic/include/clc/integer/mad_sat.h
> > new file mode 100644
> > index 0000000..3e92372
> > --- /dev/null
> > +++ b/generic/include/clc/integer/mad_sat.h
> > @@ -0,0 +1,3 @@
> > +#define __CLC_BODY <clc/integer/mad_sat.inc>
> > +#include <clc/integer/gentype.inc>
> > +#undef __CLC_BODY
> > diff --git a/generic/include/clc/integer/mad_sat.inc b/generic/include/clc/integer/mad_sat.inc
> > new file mode 100644
> > index 0000000..5da2bdf
> > --- /dev/null
> > +++ b/generic/include/clc/integer/mad_sat.inc
> > @@ -0,0 +1 @@
> > +_CLC_OVERLOAD _CLC_DECL __CLC_GENTYPE mad_sat(__CLC_GENTYPE x, __CLC_GENTYPE y, __CLC_GENTYPE z);
> > diff --git a/generic/lib/SOURCES b/generic/lib/SOURCES
> > index bfdec7b..7d3fa6b 100644
> > --- a/generic/lib/SOURCES
> > +++ b/generic/lib/SOURCES
> > @@ -19,6 +19,7 @@ integer/clz_if.ll
> > integer/clz_impl.ll
> > integer/hadd.cl
> > integer/mad24.cl
> > +integer/mad_sat.cl
> > integer/mul24.cl
> > integer/mul_hi.cl
> > integer/rhadd.cl
> > diff --git a/generic/lib/clcmacro.h b/generic/lib/clcmacro.h
> > index 730073a..ef102ea 100644
> > --- a/generic/lib/clcmacro.h
> > +++ b/generic/lib/clcmacro.h
> > @@ -41,6 +41,28 @@
> > return (RET_TYPE##16)(FUNCTION(x.lo, y.lo), FUNCTION(x.hi, y.hi)); \
> > }
> >
> > +#define _CLC_TERNARY_VECTORIZE(DECLSPEC, RET_TYPE, FUNCTION, ARG1_TYPE, ARG2_TYPE, ARG3_TYPE) \
> > + DECLSPEC RET_TYPE##2 FUNCTION(ARG1_TYPE##2 x, ARG2_TYPE##2 y, ARG3_TYPE##2 z) { \
> > + return (RET_TYPE##2)(FUNCTION(x.x, y.x, z.x), FUNCTION(x.y, y.y, z.y)); \
> > + } \
> > +\
> > + DECLSPEC RET_TYPE##3 FUNCTION(ARG1_TYPE##3 x, ARG2_TYPE##3 y, ARG3_TYPE##3 z) { \
> > + return (RET_TYPE##3)(FUNCTION(x.x, y.x, z.x), FUNCTION(x.y, y.y, z.y), \
> > + FUNCTION(x.z, y.z, z.z)); \
> > + } \
> > +\
> > + DECLSPEC RET_TYPE##4 FUNCTION(ARG1_TYPE##4 x, ARG2_TYPE##4 y, ARG3_TYPE##4 z) { \
> > + return (RET_TYPE##4)(FUNCTION(x.lo, y.lo, z.lo), FUNCTION(x.hi, y.hi, z.hi)); \
> > + } \
> > +\
> > + DECLSPEC RET_TYPE##8 FUNCTION(ARG1_TYPE##8 x, ARG2_TYPE##8 y, ARG3_TYPE##8 z) { \
> > + return (RET_TYPE##8)(FUNCTION(x.lo, y.lo, z.lo), FUNCTION(x.hi, y.hi, z.hi)); \
> > + } \
> > +\
> > + DECLSPEC RET_TYPE##16 FUNCTION(ARG1_TYPE##16 x, ARG2_TYPE##16 y, ARG3_TYPE##16 z) { \
> > + return (RET_TYPE##16)(FUNCTION(x.lo, y.lo, z.lo), FUNCTION(x.hi, y.hi, z.hi)); \
> > + }
> > +
> > #define _CLC_DEFINE_BINARY_BUILTIN(RET_TYPE, FUNCTION, BUILTIN, ARG1_TYPE, ARG2_TYPE) \
> > _CLC_DEF _CLC_OVERLOAD RET_TYPE FUNCTION(ARG1_TYPE x, ARG2_TYPE y) { \
> > return BUILTIN(x, y); \
> > diff --git a/generic/lib/integer/mad_sat.cl b/generic/lib/integer/mad_sat.cl
> > new file mode 100644
> > index 0000000..7048931
> > --- /dev/null
> > +++ b/generic/lib/integer/mad_sat.cl
> > @@ -0,0 +1,72 @@
> > +#include <clc/clc.h>
> > +#include "../clcmacro.h"
> > +
> > +_CLC_OVERLOAD _CLC_DEF char mad_sat(char x, char y, char z) {
> > + return clamp((short)mad24((short)x, (short)y, (short)z), (short)CHAR_MIN, (short) CHAR_MAX);
> > +}
> > +
> > +_CLC_OVERLOAD _CLC_DEF uchar mad_sat(uchar x, uchar y, uchar z) {
> > + return clamp((ushort)mad24((ushort)x, (ushort)y, (ushort)z), (ushort)0, (ushort) UCHAR_MAX);
> > +}
> > +
> > +_CLC_OVERLOAD _CLC_DEF short mad_sat(short x, short y, short z) {
> > + return clamp((int)mad24((int)x, (int)y, (int)z), (int)SHRT_MIN, (int) SHRT_MAX);
> > +}
> > +
> > +_CLC_OVERLOAD _CLC_DEF ushort mad_sat(ushort x, ushort y, ushort z) {
> > + return clamp((uint)mad24((uint)x, (uint)y, (uint)z), (uint)0, (uint) USHRT_MAX);
> > +}
> > +
> > +_CLC_OVERLOAD _CLC_DEF int mad_sat(int x, int y, int z) {
> > + int mhi = mul_hi(x, y);
> > + uint mlo = x * y;
> > + long m = upsample(mhi, mlo);
> > + m += z;
> > + if (m > INT_MAX)
> > + return INT_MAX;
> > + if (m < INT_MIN)
> > + return INT_MIN;
> > + return m;
> > +}
> > +
> > +_CLC_OVERLOAD _CLC_DEF uint mad_sat(uint x, uint y, uint z) {
> > + if (mul_hi(x, y) != 0)
> > + return UINT_MAX;
> > + return add_sat(x * y, z);
> > +}
> > +
> > +_CLC_OVERLOAD _CLC_DEF long mad_sat(long x, long y, long z) {
> > + long hi = mul_hi(x, y);
> > + ulong ulo = x * y;
> > + long slo = x * y;
> > + /* Big overflow of more than 2 bits, add can't fix this */
> > + if (((x < 0) == (y < 0)) && hi != 0)
> > + return LONG_MAX;
> > + /* Low overflow in mul and z not neg enough to correct it */
> > + if (hi == 0 && ulo >= LONG_MAX && (z > 0 || (ulo + z) > LONG_MAX))
> > + return LONG_MAX;
> > + /* Big overflow of more than 2 bits, add can't fix this */
> > + if (((x < 0) != (y < 0)) && hi != -1)
> > + return LONG_MIN;
> > + /* Low overflow in mul and z not pos enough to correct it */
> > + if (hi == -1 && ulo <= ((ulong)LONG_MAX + 1UL) && (z < 0 || z < (LONG_MAX - ulo)))
> > + return LONG_MIN;
> > + /* We have checked all conditions, any overflow in addtion returns
>
> s/addtion/addition/
fixed in v3
>
> The code returns all test passes on evergreen using the piglit unit
> tests for mad_sat (all data types) after I applied your LLVM
> workaround.
>
> Otherwise, I'm trying to find out if there's any redundant boolean
> logic in the above bits. Especially I'm wondering if we need to keep
> checking if hi is greater than, less than, equal to, or not equal to 0
> and -1, or if we can just pull that part out to a quick overflow test
> at the beginning.
I've tried to combine the MIN/MAX branches, but the problem is that not
all overflows are equal. Some sign bit overflows (hi is 0 or -1), can be
'corrected' by the follow up addition, so I decided to make the code
more readable and keep the cases separate.
>
> Either way, I've successfully tested this version of the code with
> your LLVM FlattenCFG.cpp patch and gotten successful unit test passes
> on CEDAR (Radeon 5400). I believe that radeonsi will probably still
> fail due to the ulong instruction selection issue that I noted
> yesterday (unless the FlattenCFG change also affects this in a
> slightly different way), but that doesn't seem like an issue with this
> patch so much as the back-end.
thanks for testing,
jan
>
> --Aaron
>
>
> > + * the correct value */
> > + return ulo + z;
> > +}
> > +
> > +_CLC_OVERLOAD _CLC_DEF ulong mad_sat(ulong x, ulong y, ulong z) {
> > + if (mul_hi(x, y) != 0)
> > + return ULONG_MAX;
> > + return add_sat(x * y, z);
> > +}
> > +
> > +_CLC_TERNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, char, mad_sat, char, char, char)
> > +_CLC_TERNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, uchar, mad_sat, uchar, uchar, uchar)
> > +_CLC_TERNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, short, mad_sat, short, short, short)
> > +_CLC_TERNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, ushort, mad_sat, ushort, ushort, ushort)
> > +_CLC_TERNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, int, mad_sat, int, int, int)
> > +_CLC_TERNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, uint, mad_sat, uint, uint, uint)
> > +_CLC_TERNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, long, mad_sat, long, long, long)
> > +_CLC_TERNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, ulong, mad_sat, ulong, ulong, ulong)
> > --
> > 1.9.3
> >
--
Jan Vesely <jan.vesely at rutgers.edu>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: This is a digitally signed message part
URL: <http://lists.llvm.org/pipermail/libclc-dev/attachments/20140805/b4084cf1/attachment.sig>
More information about the Libclc-dev
mailing list