daniel tian <daniel.xnt...@gmail.com> writes: > By the way, I don't underand the start_sequence and end_sequence. > What does those function mean. > I checked the source code in emit-rtl.c. > I still can't figure out what they do. > There is a structure sequence_stack, I don't what it does.
start_sequence and end_sequence are used to group insns into a specific location when you are generating insns. I quote the comment in emit-rtl.c: For example, consider the instruction named SPOT and the fact that we would like to emit some instructions before SPOT. We might do it like this: start_sequence (); ... emit the new instructions ... insns_head = get_insns (); end_sequence (); emit_insn_before (insns_head, SPOT); Ian