[RISCV] Passing small data limitation value to RISCV backend

Passing small data limit to RISCVELFTargetObjectFile by module flag,
So the backend can set small data section threshold by the value.
The data will be put into the small data section if the data smaller than
the threshold.

Differential Revision: https://reviews.llvm.org/D57497

1 files changed, 15 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index cd77a727231b..9a8aee1a7157 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -660,6 +660,8 @@ void CodeGenModule::Release() {
     EmitCommandLineMetadata();
 
   EmitTargetMetadata();
+
+  EmitBackendOptionsMetadata(getCodeGenOpts());
 }
 
 void CodeGenModule::EmitOpenCLMetadata() {
@@ -679,6 +681,19 @@ void CodeGenModule::EmitOpenCLMetadata() {
   OCLVerMD->addOperand(llvm::MDNode::get(Ctx, OCLVerElts));
 }
 
+void CodeGenModule::EmitBackendOptionsMetadata(
+    const CodeGenOptions CodeGenOpts) {
+  switch (getTriple().getArch()) {
+  default:
+    break;
+  case llvm::Triple::riscv32:
+  case llvm::Triple::riscv64:
+    getModule().addModuleFlag(llvm::Module::Error, "SmallDataLimit",
+                              CodeGenOpts.SmallDataLimit);
+    break;
+  }
+}
+
 void CodeGenModule::UpdateCompletedType(const TagDecl *TD) {
   // Make sure that this type is translated.
   Types.UpdateCompletedType(TD);