[llvm-exegesis] Don't use unsupported aliasing instructions

Since some instruction types aren't allowed as the main instruction also
don't allow them for aliasing instructions.

Differential Revision: https://reviews.llvm.org/D73220

diff --git a/llvm/tools/llvm-exegesis/lib/SerialSnippetGenerator.cpp b/llvm/tools/llvm-exegesis/lib/SerialSnippetGenerator.cpp
index 503c77c..3451edf 100644 (file)
--- a/llvm/tools/llvm-exegesis/lib/SerialSnippetGenerator.cpp
+++ b/llvm/tools/llvm-exegesis/lib/SerialSnippetGenerator.cpp
@@ -49,6 +49,13 @@ computeAliasingInstructions(const LLVMState &State, const Instruction *Instr,
     if (OtherOpcode == Instr->Description.getOpcode())
       continue;
     const Instruction &OtherInstr = State.getIC().getInstr(OtherOpcode);
+    const MCInstrDesc &OtherInstrDesc = OtherInstr.Description;
+    // Ignore instructions that we cannot run.
+    if (OtherInstrDesc.isPseudo() ||
+        OtherInstrDesc.isBranch() || OtherInstrDesc.isIndirectBranch() ||
+        OtherInstrDesc.isCall() || OtherInstrDesc.isReturn()) {
+          continue;
+    }
     if (OtherInstr.hasMemoryOperands())
       continue;
     if (!State.getExegesisTarget().allowAsBackToBack(OtherInstr))