[clang] [C23] Add *_NORM_MAX macros to <float.h> (PR #96643)

[Joshua Cranmer via cfe-commits]

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@@ -113,7 +113,11 @@ static T PickFP(const llvm::fltSemantics *Sem, T IEEEHalfVal, T IEEESingleVal,
 
 static void DefineFloatMacros(MacroBuilder &Builder, StringRef Prefix,
                               const llvm::fltSemantics *Sem, StringRef Ext) {
-  const char *DenormMin, *Epsilon, *Max, *Min;
+  const char *DenormMin, *NormMax, *Epsilon, *Max, *Min;
+  NormMax = PickFP(Sem, "6.5504e+4", "3.40282347e+38",
+                   "1.7976931348623157e+308", "1.18973149535723176502e+4932",
+                   "1.79769313486231580793728971405301e+308",
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jcranmer-intel wrote:

I don't think this is the correct value for ppc double-double, since double-double is supposed to give a different result for NORM_MAX than MAX (indeed, that's explicitly the point of the new macros!)

https://github.com/llvm/llvm-project/pull/96643