[llvm-branch-commits] [llvm] [BOLT][BTI] Add MCPlusBuilder::addBTItoBBStart (PR #167329)

[Gergely Bálint via llvm-branch-commits]

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@@ -1888,6 +1888,19 @@ class MCPlusBuilder {
     llvm_unreachable("not implemented");
   }
 
+  /// Checks if the indirect call / jump is accepted by the landing pad at the
+  /// start of the target BasicBlock.
+  virtual bool isBTIVariantCoveringCall(MCInst &Call, MCInst &Pad) const {
+    llvm_unreachable("not implemented");
+    return false;
+  }
+
+  /// Adds a BTI landing pad to the start of the BB, that matches the indirect
+  /// call/jump inst.
+  virtual void addBTItoBBStart(BinaryBasicBlock &BB, MCInst &Call) const {
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bgergely0 wrote:

insert is probably better. 

> (and 'ToBBStart would be a bit redundant since presumably we won't expect to insert a BTI anywhere else?)

agree. 
The naming should also imply that we don't necessarily insert a new instruction, only if the instruction already at the BBStart is not a BTI (or not compatible with a BTI). 
WDYT? 

https://github.com/llvm/llvm-project/pull/167329