1 files changed, 40 insertions, 0 deletions
diff --git a/llvm/lib/Target/X86/X86TargetMachine.cpp b/llvm/lib/Target/X86/X86TargetMachine.cpp
index d841b63a8dd..3fc528fc829 100644
--- a/llvm/lib/Target/X86/X86TargetMachine.cpp
+++ b/llvm/lib/Target/X86/X86TargetMachine.cpp
@@ -14,6 +14,7 @@
 #include "X86TargetMachine.h"
 #include "X86.h"
 #include "llvm/CodeGen/Passes.h"
+#include "llvm/IR/Function.h"
 #include "llvm/PassManager.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/FormattedStream.h"
@@ -51,6 +52,45 @@ X86TargetMachine::X86TargetMachine(const Target &T, StringRef TT, StringRef CPU,
   initAsmInfo();
 }
 
+const X86Subtarget *
+X86TargetMachine::getSubtargetImpl(const Function &F) const {
+  AttributeSet FnAttrs = F.getAttributes();
+  Attribute CPUAttr =
+      FnAttrs.getAttribute(AttributeSet::FunctionIndex, "target-cpu");
+  Attribute FSAttr =
+      FnAttrs.getAttribute(AttributeSet::FunctionIndex, "target-features");
+
+  std::string CPU = !CPUAttr.hasAttribute(Attribute::None)
+                        ? CPUAttr.getValueAsString().str()
+                        : TargetCPU;
+  std::string FS = !FSAttr.hasAttribute(Attribute::None)
+                       ? FSAttr.getValueAsString().str()
+                       : TargetFS;
+
+  // FIXME: This is related to the code below to reset the target options,
+  // we need to know whether or not the soft float flag is set on the
+  // function before we can generate a subtarget. We also need to use
+  // it as a key for the subtarget since that can be the only difference
+  // between two functions.
+  Attribute SFAttr =
+      FnAttrs.getAttribute(AttributeSet::FunctionIndex, "use-soft-float");
+  bool SoftFloat = !SFAttr.hasAttribute(Attribute::None)
+                       ? SFAttr.getValueAsString() == "true"
+                       : Options.UseSoftFloat;
+
+  auto &I = SubtargetMap[CPU + FS + (SoftFloat ? "use-soft-float=true"
+                                               : "use-soft-float=false")];
+  if (!I) {
+    // This needs to be done before we create a new subtarget since any
+    // creation will depend on the TM and the code generation flags on the
+    // function that reside in TargetOptions.
+    resetTargetOptions(F);
+    I = llvm::make_unique<X86Subtarget>(TargetTriple, CPU, FS, *this,
+                                        Options.StackAlignmentOverride);
+  }
+  return I.get();
+}
+
 //===----------------------------------------------------------------------===//
 // Command line options for x86
 //===----------------------------------------------------------------------===//