Add subtarget caches to aarch64, arm, ppc, and x86.

These will make it easier to test further changes to the
code generation and optimization pipelines as those are
moved to subtargets initialized with target feature and
target cpu.

llvm-svn: 219106

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
 //===----------------------------------------------------------------------===//