[PATCH] D157373: [RISCV] add a compress optimization for stack inst.

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: llvm/lib/Target/RISCV/RISCVFrameLowering.cpp:1304
   if (!isInt<12>(StackSize) && (CSI.size() > 0)) {
     // FirstSPAdjustAmount is chosen as (2048 - StackAlign) because 2048 will
     // cause sp = sp + 2048 in the epilogue to be split into multiple
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This comment is about the code after the compressed handling. Should it be moved down?


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Comment at: llvm/lib/Target/RISCV/RISCVFrameLowering.cpp:1324
+      // Avoid increasing extra instructions when ld/st can be compressed.
+      if ((CSI.size() <= RVCompressLen) &&
+          (StackSize <= 2048 + RVCompressLen ||
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Isn't CSI.size() the number of registers being saved? RVCompressLen is 256 or 512. Won't CSI.size() always be less than that? They aren't the same units.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D157373/new/

https://reviews.llvm.org/D157373