llvm-project

4b62afca - [X86][CodeGen] Support flags copy lowering for CCMP/CTEST (#91849)

[X86][CodeGen] Support flags copy lowering for CCMP/CTEST (#91849) ``` %1:gr64 = COPY $eflags OP1 may update eflags $eflags = COPY %1 OP2 may use eflags ``` To use eflags as input at 4th instruction, we need to use SETcc to preserve the eflags before 2, and update the source condition of OP2 according to value in GPR %1. In this patch, we support CCMP/CTEST as OP2.