[clang] [flang] [mlir] [flang,acc] Support -ffp-maxmin-behavior option in lowering. (PR #184730)

[Slava Zakharin via cfe-commits]

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@@ -47,16 +52,30 @@ def OpenACC_ReductionOperatorLogEqv  : I32EnumAttrCase<"AccEqv", 8, "eqv">;
 def OpenACC_ReductionOperatorLogNeqv : I32EnumAttrCase<"AccNeqv", 9, "neqv">;
 def OpenACC_ReductionOperatorLogAnd  : I32EnumAttrCase<"AccLand", 10, "land">;
 def OpenACC_ReductionOperatorLogOr   : I32EnumAttrCase<"AccLor", 11, "lor">;
-
-def OpenACC_ReductionOperator : I32EnumAttr<"ReductionOperator",
-    "built-in reduction operations supported by OpenACC",
-    [OpenACC_ReductionOperatorNone, OpenACC_ReductionOperatorAdd, 
-     OpenACC_ReductionOperatorMul, OpenACC_ReductionOperatorMax, OpenACC_ReductionOperatorMin,
-     OpenACC_ReductionOperatorAnd, OpenACC_ReductionOperatorOr,
-     OpenACC_ReductionOperatorXor, OpenACC_ReductionOperatorLogEqv,
-     OpenACC_ReductionOperatorLogNeqv, OpenACC_ReductionOperatorLogAnd,
-     OpenACC_ReductionOperatorLogOr
-    ]> {
+// The following reduction operators correspond to arith::AtomicRMWKind kinds
+// named alike. They can only be applied to floating-point types.
+// These reductions can be auto-parallelized.
+def OpenACC_ReductionOperatorMaximum
+    : I32EnumAttrCase<"AccMaximumf", 12, "maximumf">;
+def OpenACC_ReductionOperatorMinimum
+    : I32EnumAttrCase<"AccMinimumf", 13, "minimumf">;
+def OpenACC_ReductionOperatorMaxnum
+    : I32EnumAttrCase<"AccMaxnumf", 14, "maxnumf">;
+def OpenACC_ReductionOperatorMinnum
+    : I32EnumAttrCase<"AccMinnumf", 15, "minnumf">;
+
+def OpenACC_ReductionOperator
+    : I32EnumAttr<
+          "ReductionOperator",
+          "built-in reduction operations supported by OpenACC",
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vzakhari wrote:

I added a comment. I tried modifying the `summary` string, but it looks like tablegen only supports single line here. Moreover, the summary string ends up being printed by verifier in case of error, so having too much detail there is impractical.

https://github.com/llvm/llvm-project/pull/184730