llvm-project

ff5fa711 - [AArch64][SVE] Tweak how SVE CFI expressions are emitted (#151677)

[AArch64][SVE] Tweak how SVE CFI expressions are emitted (#151677) The main change in this patch is we go from emitting the expression: @ cfa - NumBytes - NumScalableBytes * VG To: @ cfa - VG * NumScalableBytes - NumBytes That is, VG is the first expression. This is for a future patch that adds an alternative way to resolve VG (which uses the CFA, so it is convenient for the CFA to be at the top of the stack). Since doing this is fairly churn-heavy, I took the opportunity to also save up to 4-bytes per SVE CFI expression. This is done by folding LEB128 constants to literals when in the range 0 to 31, and using the offset in `DW_OP_breg*` expressions.