[PATCH] D61626: [RISCV] Disable tail call if the callee function contain __builtin_frame_address or __builtin_return_address

[Mandeep Singh Grang via Phabricator via llvm-commits]

mgrang added inline comments.


================
Comment at: lib/Target/RISCV/RISCVISelLowering.cpp:1312
+// Return frame depth argument of __builtin_frame_address or
+// __builtin_return_address
+static unsigned getFrameDepthArg(const Instruction *I) {
----------------
Period at the end of comment.


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Comment at: lib/Target/RISCV/RISCVISelLowering.cpp:1415
+    const Function *CalleeFn = dyn_cast<Function>(G->getGlobal());
+    if (CalleeFn)
+      for (const BasicBlock &BB : *CalleeFn)
----------------
This check can be combined with the assignment:
if (const Function *CalleeFn = dyn_cast<Function>(G->getGlobal()))


================
Comment at: lib/Target/RISCV/RISCVISelLowering.cpp:1419
+          if (isFrameAddressOrReturnAddressCall(&I) &&
+              (getFrameDepthArg(&I) > 0))
+            return false;
----------------
getFrameDepthArg asserts on isFrameAddressOrReturnAddressCall. So we end up calling isFrameAddressOrReturnAddressCall twice here. We could put them into one function but it is cleaner the way it is now.
@asb Do you think this should be cleaned up?


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D61626/new/

https://reviews.llvm.org/D61626