Hi Yongchong, You should be able to use target-specific variable assignment to avoid rewriting the rules:
defgu2s: CFLAGS += -OPT:ro=1 See: http://www.gnu.org/software/make/manual/html_node/Target_002dspecific.html#Target_002dspecific Two things I am unclear on: 1. The change is specific to IA64. Wouldn't this be a problem for other targets, too? 2. What if you are building the library in debug mode? Should the flag change also be conditional on -O3 existing in CFLAGS? -David Coakley / AMD Open Source Compiler Engineering On Thu, Mar 3, 2011 at 12:34 AM, Wu Yongchong <wuyongch...@gmail.com> wrote: > can a gatekeeper help review this patch > > This is a round off issue in IA64 system relative open64 library, the > libffio.a. > > we use opencc -O3 to build libffio.a, the round off option in -O3 is > -OPT:ro=2, it allow reassociation transforma\ > tions. > > in line 531 of file osprey/libu/numconv/mpp/defgu2s.c > > expression > pre_result = a*x + (a*y + x*b +(b*y > + (table_high*exact_low_number + > exact_high_number*table_low + > table_low*exact_low_number))); > > the compiler will re-associated it to > > pre_result = (a*x + a*y + x*b + b*y) + > (table_high*exact_low_number + > exact_high_number*table_low + > table_low*exact_low_number); > > so do the precision of pre_result, this difference may affect the > result of 200.sixtrack and them get outp\ > ut difference error. > > Here is my patch, I just add -OPT:ro=1 to make file defgu2s.c when > building library libffio.a > > =================================================================== > --- osprey/libu/Makefile.gbase (revision 3495) > +++ osprey/libu/Makefile.gbase (working copy) > @@ -358,3 +358,15 @@ > ./massage > numbers.h > endif > > +ifeq ($(BUILD_ARCH), IA64) > + ifeq ($(BUILD_COMPILER), OSP) > +defgu2s.o : defgu2s.c > + $(cc) -c $(CPPFLAGS) $(CFLAGS) -OPT:ro=1 $< -o $@ > + > +defgu2s.pic.o : defgu2s.c > + $(cc) $(pic_flag) -c $(CPPFLAGS) $(CFLAGS) -OPT:ro=1 $< -o $@ > + > +defgu2s.pg.o : defgu2s.c > + $(cc) $(prof_flag) -c $(CPPFLAGS) $(CFLAGS) -OPT:ro=1 $< -o $@ > + endif > +endif > \ No newline at end of file > > -- > yongchong > > ------------------------------------------------------------------------------ > Free Software Download: Index, Search & Analyze Logs and other IT data in > Real-Time with Splunk. Collect, index and harness all the fast moving IT data > generated by your applications, servers and devices whether physical, virtual > or in the cloud. Deliver compliance at lower cost and gain new business > insights. http://p.sf.net/sfu/splunk-dev2dev > _______________________________________________ > Open64-devel mailing list > Open64-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/open64-devel > ------------------------------------------------------------------------------ What You Don't Know About Data Connectivity CAN Hurt You This paper provides an overview of data connectivity, details its effect on application quality, and explores various alternative solutions. http://p.sf.net/sfu/progress-d2d _______________________________________________ Open64-devel mailing list Open64-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/open64-devel
