[llvm] e65c5ee - [AArch64] Make opcode switch in tryARM64PackedUnwind comprehensive.

[Eli Friedman via llvm-commits]

Author: Eli Friedman
Date: 2022-12-01T12:06:31-08:00
New Revision: e65c5eebb8ed534b4575878e42e532389dcb5a2c

URL: https://github.com/llvm/llvm-project/commit/e65c5eebb8ed534b4575878e42e532389dcb5a2c
DIFF: https://github.com/llvm/llvm-project/commit/e65c5eebb8ed534b4575878e42e532389dcb5a2c.diff

LOG: [AArch64] Make opcode switch in tryARM64PackedUnwind comprehensive.

I don't think compiler-generated code could actually be affected by
this, but better to be thorough.

Differential Revision: https://reviews.llvm.org/D139048

Added: 
    

Modified: 
    llvm/lib/MC/MCWin64EH.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/MC/MCWin64EH.cpp b/llvm/lib/MC/MCWin64EH.cpp
index 99722704ac50..5102d48b3a5d 100644
--- a/llvm/lib/MC/MCWin64EH.cpp
+++ b/llvm/lib/MC/MCWin64EH.cpp
@@ -999,6 +999,23 @@ static bool tryARM64PackedUnwind(WinEH::FrameInfo *info, uint32_t FuncLength,
       // These are never canonical; they don't show up with the usual Arm64
       // calling convention.
       return false;
+    case Win64EH::UOP_AllocLarge:
+      // Allocations this large can't be represented in packed unwind (and
+      // usually don't fit the canonical form anyway because we need to use
+      // __chkstk to allocate the stack space).
+      return false;
+    case Win64EH::UOP_AddFP:
+      // "add x29, sp, #N" doesn't show up in the canonical pattern (except for
+      // N=0, which is UOP_SetFP).
+      return false;
+    case Win64EH::UOP_TrapFrame:
+    case Win64EH::UOP_Context:
+    case Win64EH::UOP_ClearUnwoundToCall:
+    case Win64EH::UOP_PushMachFrame:
+      // These are special opcodes that aren't normally generated.
+      return false;
+    default:
+      report_fatal_error("Unknown Arm64 unwind opcode");
     }
   }
   if (RegI > 10 || RegF > 8)