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digitalmars.D.learn - Question about Vectors

reply "Charles" <csmith.ku2013 gmail.com> writes:
So I was reading the documentation page: 
http://dlang.org/simd.html and noticed what appears to be a typo:

int4 v;
(cast(int*)&v)[3] = 2;   // set 3rd element of the 4 int vector
(cast(int[4])v)[3] = 2;  // set 3rd element of the 4 int vector
v.array[3] = 2;          // set 3rd element of the 4 int vector
v.ptr[3] = 2;            // set 3rd element of the 4 int vector

v.array[3] = 2; and v.ptr[3] = 2; set the fourth element, and not 
the third.

As I was verifying this, I realized I had to compile it in 64 bit 
code. The 32 bit code produced the error "SIMD vector types not 
supported on this platform".

My test code is:

     void main() {
         import std.stdio;
         import core.simd;

         int4 v = 7;
         v.ptr[3] = 2;
         writeln(v.array[]);
     }


Is that related to me compiling while using a 64 bit OS, or is 
that true of any 32 bit OS, and thus, vectors can't be used in 
programs intended to be run on 32 bit OSs?

Thanks,
Charles
Nov 20 2014
parent Marco Leise <Marco.Leise gmx.de> writes:
Am Thu, 20 Nov 2014 20:17:31 +0000
schrieb "Charles" <csmith.ku2013 gmail.com>:

 So I was reading the documentation page: 
 http://dlang.org/simd.html and noticed what appears to be a typo:
 
 int4 v;
 (cast(int*)&v)[3] = 2;   // set 3rd element of the 4 int vector
 (cast(int[4])v)[3] = 2;  // set 3rd element of the 4 int vector
 v.array[3] = 2;          // set 3rd element of the 4 int vector
 v.ptr[3] = 2;            // set 3rd element of the 4 int vector
 
 v.array[3] = 2; and v.ptr[3] = 2; set the fourth element, and not 
 the third.
 
 As I was verifying this, I realized I had to compile it in 64 bit 
 code. The 32 bit code produced the error "SIMD vector types not 
 supported on this platform".
 
 My test code is:
 
      void main() {
          import std.stdio;
          import core.simd;
 
          int4 v = 7;
          v.ptr[3] = 2;
          writeln(v.array[]);
      }
 
 
 Is that related to me compiling while using a 64 bit OS, or is 
 that true of any 32 bit OS, and thus, vectors can't be used in 
 programs intended to be run on 32 bit OSs?
 
 Thanks,
 Charles
DMD supports SIMD only on amd64, but you can use the GDC or LDC2 compilers if you need 32-bit support for vector types. -- Marco
Nov 21 2014