Programming-Guides/Porting_Vector_Intrinsics/sec_power_vmx.xml

<?xml version="1.0" encoding="UTF-8"?>
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<section xmlns="http://docbook.org/ns/docbook"
  xmlns:xi="http://www.w3.org/2001/XInclude"
  xmlns:xlink="http://www.w3.org/1999/xlink"
  version="5.0"
  xml:id="sec_power_vmx">
  <title>The Vector Facility (VMX)</title>
  
 <para>The original VMX supported SIMD integer byte, halfword, and word, and 
  single float data types within a separate (from GPR and FPR) bank of 32 x 
  128-bit vector registers. The arithmetic operations like to stay within their (SIMD) 
  lanes except where the operation changes the element data size (integer 
  multiply) or the generalized permute operations
  (splat, permute, pack, unpack merge). </para>

  <para>This is complemented by bit logical and shift / rotate instructions
  that operate on the vector as a whole.  Some operations
  (permute, pack, merge, shift double, select) will select 128 bits from a pair 
  of vectors (256-bits) and delivers a 128-bit vector result. These instructions 
  will cross lanes or multiple registers to grab fields and assemble them into 
  the single register result.</para>

  <para>The PowerISA 2.07B Chapter 6. Vector Facility is organised starting 
  with an overview (chapters 6.1- 6.6):

  <literallayout><literal>
6.1 Vector Facility Overview . . . . . . . . . . . . . . . . . . . . 227
6.2 Chapter Conventions. . . . . . . . . . . . . . . . . . . . . . . 227
6.2.1 Description of Instruction Operation . . . . . . . . . . . . . 227
6.3 Vector Facility Registers  . . . . . . . . . . . . . . . . . . . 234
6.3.1 Vector Registers . . . . . . . . . . . . . . . . . . . . . . . 234
6.3.2 Vector Status and Control Register . . . . . . . . . . . . . . 234
6.3.3 VR Save Register . . . . . . . . . . . . . . . . . . . . . . . 235
6.4 Vector Storage Access Operations . . . . . . . . . . . . . . . . 235
6.4.1 Accessing Unaligned Storage Operands . . . . . . . . . . . . . 237
6.5 Vector Integer Operations  . . . . . . . . . . . . . . . . . . . 238
6.5.1 Integer Saturation . . . . . . . . . . . . . . . . . . . . . . 238
6.6 Vector Floating-Point Operations . . . . . . . . . . . . . . . . 240
6.6.1 Floating-Point Overview  . . . . . . . . . . . . . . . . . . . 240
6.6.2 Floating-Point Exceptions  . . . . . . . . . . . . . . . . . . 240
  </literal></literallayout></para>
  
  <para>Then a chapter on storage (load/store) access for vector and vector 
  elements:

  <literallayout><literal>
6.7 Vector Storage Access Instructions . . . . . . . . . . . . . . . 242
6.7.1 Storage Access Exceptions  . . . . . . . . . . . . . . . . . . 242
6.7.2 Vector Load Instructions . . . . . . . . . . . . . . . . . . . 243
6.7.3 Vector Store Instructions. . . . . . . . . . . . . . . . . . . 246
6.7.4 Vector Alignment Support Instructions. . . . . . . . . . . . . 248
  </literal></literallayout></para>
  
  <xi:include href="sec_power_vector_permute_format.xml"/>

</section>