[llvm-exegesis] Mark second-form X87 instructions as unsupported.
Summary:
We only support the first form because we rely on information that is
only available there.
Reviewers: gchatelet
Subscribers: tschuett, llvm-commits
Differential Revision: https://reviews.llvm.org/D53430
llvm-svn: 344782
diff --git a/llvm/tools/llvm-exegesis/lib/X86/Target.cpp b/llvm/tools/llvm-exegesis/lib/X86/Target.cpp
index ae5c2e8..1a7d290 100644
--- a/llvm/tools/llvm-exegesis/lib/X86/Target.cpp
+++ b/llvm/tools/llvm-exegesis/lib/X86/Target.cpp
@@ -26,7 +26,14 @@
if (OpcodeName.startswith("POPF") || OpcodeName.startswith("PUSHF") ||
OpcodeName.startswith("ADJCALLSTACK"))
return llvm::make_error<BenchmarkFailure>(
- "Unsupported opcode: Push/Pop/AdjCallStack");
+ "unsupported opcode: Push/Pop/AdjCallStack");
+ // We do not handle second-form X87 instructions. We only handle first-form
+ // ones (_Fp), see comment in X86InstrFPStack.td.
+ for (const Operand &Op : Instr.Operands)
+ if (Op.isReg() && Op.isExplicit() &&
+ Op.getExplicitOperandInfo().RegClass == llvm::X86::RSTRegClassID)
+ return llvm::make_error<BenchmarkFailure>(
+ "unsupported second-form X87 instruction");
return llvm::Error::success();
}