[llvm] [IR] Store fast-math flags in subclasses of Instruction (PR #191190)

[Alexis Engelke via llvm-commits]

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@@ -284,54 +289,63 @@ class FPMathOperator : public Operator {
 public:
   /// Test if this operation allows all non-strict floating-point transforms.
   bool isFast() const {
-    return ((SubclassOptionalData & FastMathFlags::AllowReassoc) != 0 &&
-            (SubclassOptionalData & FastMathFlags::NoNaNs) != 0 &&
-            (SubclassOptionalData & FastMathFlags::NoInfs) != 0 &&
-            (SubclassOptionalData & FastMathFlags::NoSignedZeros) != 0 &&
-            (SubclassOptionalData & FastMathFlags::AllowReciprocal) != 0 &&
-            (SubclassOptionalData & FastMathFlags::AllowContract) != 0 &&
-            (SubclassOptionalData & FastMathFlags::ApproxFunc) != 0);
+    unsigned short FMFValue = getFMFValue();
+    return ((FMFValue & FastMathFlags::AllowReassoc) != 0 &&
+            (FMFValue & FastMathFlags::NoNaNs) != 0 &&
+            (FMFValue & FastMathFlags::NoInfs) != 0 &&
+            (FMFValue & FastMathFlags::NoSignedZeros) != 0 &&
+            (FMFValue & FastMathFlags::AllowReciprocal) != 0 &&
+            (FMFValue & FastMathFlags::AllowContract) != 0 &&
+            (FMFValue & FastMathFlags::ApproxFunc) != 0);
   }
 
   /// Test if this operation may be simplified with reassociative transforms.
   bool hasAllowReassoc() const {
-    return (SubclassOptionalData & FastMathFlags::AllowReassoc) != 0;
+    unsigned short FMFValue = getFMFValue();
+    return (FMFValue & FastMathFlags::AllowReassoc) != 0;
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aengelke wrote:

The refactoring away from SubclassOptionalData to a wrapper function (why not use getFastMathFlags() here?) could be done as a separate PR before this.

https://github.com/llvm/llvm-project/pull/191190