------- Comment #8 from anitha dot boyapati at atmel dot com 2010-08-23 13:25 ------- When -O2 is enabled result is 0xFF (255) which is incorrect. The code generated for the following shift operation:
13: return (left << right); +000000AB: C004 RJMP PC+0x0005 Relative jump +000000AC: 0F22 LSL R18 Logical Shift Left +000000AD: 1F33 ROL R19 Rotate Left Through Carry +000000AE: 1F44 ROL R20 Rotate Left Through Carry +000000AF: 1F55 ROL R21 Rotate Left Through Carry +000000B0: 952A DEC R18 Decrement +000000B1: F7D2 BRPL PC-0x05 Branch if plus 19: g_6= func_1 (g_6, g_6); +000000B2: 93200100 STS 0x0100,R18 Store direct to data space 'left' is stored in registers R21:R20:R19:R18 as it is typecasted to uint32_t type while 'right' is stored in R18. Because of shift logic, R18 becomes 0xFF in first iteration which is then stored. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39386
