[CLN-list] cln: MIPS release 6 support patch

[YunQiang Su]

We are working on MIPS release 6 port of Debian, and fix a problem of cln.

MIPS release 6 is not full compatible with the previous releases, it removes
some instructions and changes encoding of some instruction.
the `multu' is included.

MIPS r6 drops `lo' and `hi' registers, and then removes `multu'/`mfhi'/`mflo'.
Instead it uses `mulu' to compute the low part and `muhu' to compute
the high part.


Index: cln-1.3.4/src/base/cl_low.h
===================================================================
--- cln-1.3.4.orig/src/base/cl_low.h
+++ cln-1.3.4/src/base/cl_low.h
@@ -273,10 +273,15 @@ inline uint32 mulu32_unchecked (uint32 a
        unused (hi_zuweisung _hi); lo_zuweisung _lo;              \
      })
 #elif defined(__GNUC__) && defined(__mips__) && !defined(NO_ASM)
+ #if __mips_isa_rev >= 6
+  #define MULTU_HI_LO "mulu %1,%3,%2 ; muhu %0,%3,%2"
+ #else
+  #define MULTU_HI_LO "multu %3,%2 ; mfhi %0 ; mflo %1"
+ #endif
   #define mulu32(x,y,hi_zuweisung,lo_zuweisung)  \
     ({ var register uint32 _hi;                       \
        var register uint32 _lo;                       \
-       __asm__("multu %3,%2 ; mfhi %0 ; mflo %1"      \
+       __asm__(MULTU_HI_LO                            \
                : "=r" (_hi), "=r" (_lo)               \
                : "r" ((uint32)(x)), "r" ((uint32)(y)) \
               );                                      \
Index: cln-1.3.4/src/base/digitseq/cl_asm_mips_.cc
===================================================================
--- cln-1.3.4.orig/src/base/digitseq/cl_asm_mips_.cc
+++ cln-1.3.4/src/base/digitseq/cl_asm_mips_.cc
@@ -88,9 +88,14 @@
         DECLARE_FUNCTION(mulu32_)
         .ent mulu32_ // Input in $4,$5, Output in $2,mulu32_high
 mulu32_:
+#if __mips_isa_rev >= 6
+        mulu $2,$5,$4           // arg1 * arg2, lo
+        muhu $6,$5,$4           // arg1 * arg2, hi
+#else
         multu $5,$4             // arg1 * arg2
         mfhi $6                 // hi
         mflo $2                 // lo
+#endif
         sw $6,mulu32_high       // hi abspeichern // Adressierung??
Deklaration??
         j $31                   // return
         .end mulu32_

-- 
YunQiang Su