[dev.cc] liblink: more docs on Prog and Addr fields

LGTM=rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/174530043

diff --git a/include/link.h b/include/link.h
index 33a66e93cbbc76666e8bfc209bf688d90dcbc893..2b1d02102b5f5505a172b75ba63f8fdd324735cb 100644 (file)
--- a/include/link.h
+++ b/include/link.h
@@ -62,7 +62,7 @@ struct        Addr
        short   type;
        uint8   index;
        int8    scale;
-       int8    reg;    // for 5l, 9l
+       int8    reg;    // for 5l, 9l; GPRs and FPRs both start at 0
        int8    name; // for 5l, 9l
        int8    class;  // for 5l, 9l
        uint8   etype; // for 5g, 6g, 8g
@@ -94,6 +94,7 @@ struct        Prog
        // operands
        Addr    from;
        uchar   reg; // arm, power64 only (e.g., ADD from, reg, to);
+                    // starts at 0 for both GPRs and FPRs;
                     // also used for ADATA width on arm, power64
        Addr    from3; // power64 only (e.g., RLWM/FMADD from, reg, from3, to)
        Addr    to;