Inline refactoring: move state machine into LegacyPolicy

The state machine used to estimate callee native code size is now an
internal part of the LegacyPolicy.

During `fgFindJumpTargets` the policy determines if the state machine
is need, and if so, sets one up. `fgFindJumpTargets` then notifies the
policy of the various opcodes in the method, and the policy uses this
to drive the state machine forward.

When the IL scan is completed, the `fgFindJumpTargets` notifies the
policy, then, for the discretionary inline case, grabs the native size
estimate, and uses that to evaluate inlinability.

The knowledge of when inlines are "always", "forced", or
"discretionary" is now encapsulated by the policy instead of being
distributed in various places in the code.

1 files changed, 22 insertions, 12 deletions

diff --git a/src/jit/inlinepolicy.h b/src/jit/inlinepolicy.h
index 4f831a1e77..45faba9085 100644
--- a/src/jit/inlinepolicy.h
+++ b/src/jit/inlinepolicy.h
@@ -17,6 +17,8 @@
 #include "jit.h"
 #include "inline.h"
 
+class CodeSeqSM;
+
 // LegacyPolicy implements the inlining policy used by the jit in its
 // initial release.
 //
@@ -39,6 +41,9 @@ public:
     LegacyPolicy(Compiler* compiler, bool isPrejitRoot)
         : InlinePolicy(isPrejitRoot)
         , inlCompiler(compiler)
+        , inlStateMachine(nullptr)
+        , inlCodeSize(0)
+        , inlNativeSizeEstimate(NATIVE_SIZE_INVALID)
         , inlIsForceInline(false)
         , inlIsForceInlineKnown(false)
         , inlIsInstanceCtor(false)
@@ -55,13 +60,15 @@ public:
 
     // Policy observations
     void noteSuccess() override;
-    void noteFatal(InlineObservation obs) override;
     void noteBool(InlineObservation obs, bool value) override;
+    void noteFatal(InlineObservation obs) override;
     void noteInt(InlineObservation obs, int value) override;
     void noteDouble(InlineObservation obs, double value) override;
 
     // Policy determinations
     double determineMultiplier() override;
+    int determineNativeSizeEstimate() override;
+    bool hasNativeSizeEstimate() override;
 
     // Policy policies
     bool propagateNeverToRuntime() const override { return true; }
@@ -82,17 +89,20 @@ private:
     const unsigned MAX_BASIC_BLOCKS = 5;
 
     // Data members
-    Compiler* inlCompiler;
-    bool      inlIsForceInline :1;
-    bool      inlIsForceInlineKnown :1;
-    bool      inlIsInstanceCtor :1;
-    bool      inlIsFromPromotableValueClass :1;
-    bool      inlHasSimd :1;
-    bool      inlLooksLikeWrapperMethod :1;
-    bool      inlArgFeedsConstantTest :1;
-    bool      inlMethodIsMostlyLoadStore :1;
-    bool      inlArgFeedsRangeCheck :1;
-    bool      inlConstantFeedsConstantTest :1;
+    Compiler*  inlCompiler;
+    CodeSeqSM* inlStateMachine;
+    unsigned   inlCodeSize;
+    int        inlNativeSizeEstimate;
+    bool       inlIsForceInline :1;
+    bool       inlIsForceInlineKnown :1;
+    bool       inlIsInstanceCtor :1;
+    bool       inlIsFromPromotableValueClass :1;
+    bool       inlHasSimd :1;
+    bool       inlLooksLikeWrapperMethod :1;
+    bool       inlArgFeedsConstantTest :1;
+    bool       inlMethodIsMostlyLoadStore :1;
+    bool       inlArgFeedsRangeCheck :1;
+    bool       inlConstantFeedsConstantTest :1;
 };
 
 #endif // _INLINE_POLICY_H_