Syntax on inline PTX code for CUDA
===

As written in Nvidia's Inline PTX Assembly document, the grammar for using inline assembly is:
<code>asm("temp_string" : "constraint"(output) : "constraint"(input));</code>  
Here are two examples:  
<code>asm("vadd.s32.s32.s32 %0, %1.h0, %2.h0;" : "=r"(v) : "r"(a), "r"(b));</code>  
<code>asm("vadd.u32.u32.u32 %0.b0, %1, %2, %3;" : "=r"(v) : "r"(a), "r"(b), "r"(z));</code>  
In both examples, there are parameters such as:<code>h0</code> or <code>b0</code> follow the <code>%n</code>. I looked through CUDA's official document and didn't find anything concerns about the meaning of <code>h0</code> or <code>b0</code>. I've seen <code>h0</code>,<code>h1</code> and <code>b0</code>,<code>b1</code>,<code>b2</code>,<code>b3</code>. I guess <code>h0</code> or <code>h1</code> represents a 16bit value, while <code>bn</code> represents a byte value. Does someone know the exact meaning of these?
