contrib: mad: import debian patch for thumb2

contrib/src/mad/Provide-Thumb-2-alternative-code-for-MAD_F_MLN.diff

+From: Dave Martin
+Subject: "rsc" doesnt exist anymore in thumb2
+
+diff --git a/fixed.h b/fixed.h
+index 4b58abf..ba4bc26 100644
+--- a/fixed.h
++++ b/fixed.h
+@@ -275,12 +275,25 @@ mad_fixed_t mad_f_mul_inline(mad_fixed_t x, mad_fixed_t y)
+ 	 : "+r" (lo), "+r" (hi)  \
+ 	 : "%r" (x), "r" (y))
+ 
++#ifdef __thumb__
++/* In Thumb-2, the RSB-immediate instruction is only allowed with a zero
++	operand.  If needed this code can also support Thumb-1 
++	(simply append "s" to the end of the second two instructions). */
++#  define MAD_F_MLN(hi, lo)  \
++    asm ("rsbs        %0, %0, #0\n\t"  \
++	 "sbc   %1, %1, %1\n\t"  \
++	 "sub   %1, %1, %2"  \
++	 : "+&r" (lo), "=&r" (hi)  \
++	 : "r" (hi)  \
++	 : "cc")
++#else /* ! __thumb__ */
+ #  define MAD_F_MLN(hi, lo)  \
+     asm ("rsbs	%0, %2, #0\n\t"  \
+ 	 "rsc	%1, %3, #0"  \
+-	 : "=r" (lo), "=r" (hi)  \
++	 : "=&r" (lo), "=r" (hi)  \
+ 	 : "0" (lo), "1" (hi)  \
+ 	 : "cc")
++#endif /* __thumb__ */
+ 
+ #  define mad_f_scale64(hi, lo)  \
+     ({ mad_fixed_t __result;  \

contrib/src/mad/rules.mak

@@ -25,15 +25,16 @@ ifdef HAVE_IOS
 	$(APPLY) $(SRC)/mad/mad-ios-asm.patch
 endif
 	$(APPLY) $(SRC)/mad/mad-noopt.patch
+	$(APPLY) $(SRC)/mad/Provide-Thumb-2-alternative-code-for-MAD_F_MLN.diff
 	$(MOVE)
 
 .mad: libmad
 	touch libmad/NEWS libmad/AUTHORS libmad/ChangeLog
 	$(RECONF)
 ifdef HAVE_IOS
-	cd $< && $(HOSTVARS) CCAS="$(AS)" CFLAGS="$(CFLAGS) -O4 -marm $(NOTHUMB)" ./configure $(HOSTCONF) $(MAD_CONF)
+	cd $< && $(HOSTVARS) CCAS="$(AS)" CFLAGS="$(CFLAGS) -O4" ./configure $(HOSTCONF) $(MAD_CONF)
 else
-	cd $< && $(HOSTVARS) CFLAGS="$(CFLAGS) -O3 $(NOTHUMB)" ./configure $(HOSTCONF) $(MAD_CONF)
+	cd $< && $(HOSTVARS) CFLAGS="$(CFLAGS) -O3" ./configure $(HOSTCONF) $(MAD_CONF)
 endif
 	cd $< && $(MAKE) install
 	touch $@