[PATCH] D125648: [ARM SEH 6] [ARM] Add SEH opcodes in frame lowering

[Martin Storsjö via Phabricator via llvm-commits]

mstorsjo added inline comments.


================
Comment at: llvm/lib/Target/ARM/ARMFrameLowering.cpp:1126
+        // contain a stable frame pointer, thus manually insert a .seh_nop
+        // here instead.
+        auto SEH = BuildMI(MF, dl, TII.get(ARM::SEH_Nop))
----------------
efriedma wrote:
> We shouldn't be encoding stack realignment into the unwind data.  It's basically a dynamic allocation: we have to emit a frame pointer before we realign the stack, and we should cut off the unwind prologue immediately after the frame pointer is set up.
Right, that'd be even cleaner. (This part gets tested only in the next patch which tweaks the frame pointers, and all the later opcodes are nops in that case. So cutting off the prologue at that point sounds like a good strategy.)


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  https://reviews.llvm.org/D125648/new/

https://reviews.llvm.org/D125648