[PATCH] D153098: [AArch64] Emit fewer CFI instructions for synchronous unwind tables

[Igor Kudrin via Phabricator via llvm-commits]

ikudrin added inline comments.


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Comment at: llvm/test/CodeGen/AArch64/addsub-constant-folding.ll:363
 ; CHECK-NEXT:    sub sp, sp, #32
-; CHECK-NEXT:    .cfi_def_cfa_offset 32
 ; CHECK-NEXT:    str x30, [sp, #16] // 8-byte Folded Spill
+; CHECK-NEXT:    .cfi_def_cfa_offset 32
----------------
MaskRay wrote:
> `.cfi_def_cfa_offset 32` move like this seems unnecessary. It degrades precision without reducing the number of CFI instructions for sync.
The goal is to reduce the size of the unwind table, not just the number of CFI instructions. Having only one chunk removes `DWA_CFA_advance_loc` instructions that would otherwise be required.


Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D153098/new/

https://reviews.llvm.org/D153098