http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50814
Bug #: 50814 Summary: SH Target: SHAD / SHLD instructions not used on SH2A Classification: Unclassified Product: gcc Version: 4.7.0 Status: UNCONFIRMED Severity: enhancement Priority: P3 Component: target AssignedTo: unassig...@gcc.gnu.org ReportedBy: oleg.e...@t-online.de CC: kkoj...@gcc.gnu.org Target: sh2a-*-* Although there are some insns (e.g. ashlsi3_sh2a) that are supposed to handle dynamic shifts on SH2A, somehow the dynamic shift instructions SHAD and SHLD are never generated, no matter what the shift amount is. int x_shad_right (int y) { return y >> 15; } mov.l .L6,r1 sts.l pr,@-r15 jsr @r1 nop mov r4,r0 lds.l @r15+,pr rts/n .align 2 .L6: .long ___ashiftrt_r4_15 int x_shad_left (int y) { return y << 15; } mov r4,r0 shll8 r0 shlr r0 rts shll8 r0 Using built-in specs. COLLECT_GCC=sh-elf-gcc COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/sh-elf/4.7.0/lto-wrapper Target: sh-elf Configured with: ../gcc-trunk/configure --target=sh-elf --prefix=/usr/local --enable-languages=c,c++ --enable-multilib --disable-libssp --disable-nls --disable-werror --enable-lto --with-newlib --with-gnu-as --with-gnu-ld --with-system-zlib Thread model: single gcc version 4.7.0 20111020 (experimental) (GCC) It is also not clear to me why SH2A seems to require different handling for dynamic shifts than SH3 or SH4...