Hi, I'd appreciate if someone could advise me in builtin expansion I'm currently writing.
High level description for what I want to do: I have 2 operands in my builtin. First I set register (reg1) with value from operand1 (op1); Second I call my instruction (reg1 is called implicitly and updated); At the end I'm setting operand2 (op2) with value from reg1. Simplified implementation in i386.c I have: reg1 = gen_reg_rtx (mode); emit_insn (gen_rtx_SET (reg1, op1); emit_clobber (reg1); emit_insn (gen_myinstruction ()); emit_insn (gen_rtx_SET (op2,reg1)); Everything works fine for -O0, but when I move to higher level optimizations setting value into reg1 (lines before emit_clobber) are optimized out. I already tried moving emit_clobber just after assignment but it doesn't help. Could you please suggest how I can prevent it from happening? Thanks, Sebastian
