[llvm-exegesis] Get the BenchmarkRunner from the ExegesisTarget.

Summary:
This allows targets to override code generation for some instructions.
As an example of override, this also moves ad-hoc instruction filtering
for X86 into the X86 ExegesisTarget.

Reviewers: gchatelet

Subscribers: mgorny, tschuett, llvm-commits

Differential Revision: https://reviews.llvm.org/D48587

llvm-svn: 335582

1 files changed, 5 insertions, 0 deletions

diff --git a/llvm/tools/llvm-exegesis/lib/LlvmState.cpp b/llvm/tools/llvm-exegesis/lib/LlvmState.cpp
index 9b30d78b0c9..9ff42ca71fd 100644
--- a/llvm/tools/llvm-exegesis/lib/LlvmState.cpp
+++ b/llvm/tools/llvm-exegesis/lib/LlvmState.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "LlvmState.h"
+#include "Target.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/MC/MCCodeEmitter.h"
 #include "llvm/MC/MCContext.h"
@@ -30,6 +31,10 @@ LLVMState::LLVMState(const std::string &Triple, const std::string &CpuName) {
       TheTarget->createTargetMachine(Triple, CpuName, /*Features*/ "", Options,
                                      llvm::Reloc::Model::Static)));
   TheExegesisTarget = ExegesisTarget::lookup(TargetMachine->getTargetTriple());
+  if (!TheExegesisTarget) {
+    llvm::errs() << "no exegesis target for " << Triple << ", using default\n";
+    TheExegesisTarget = &ExegesisTarget::getDefault();
+  }
 }
 
 LLVMState::LLVMState()