[clang] [flang] [llvm] Introduce -fexperimental-loop-fuse to clang and flang (PR #142686)

[Fangrui Song via llvm-commits]

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@@ -1671,6 +1671,11 @@ void CompilerInvocationBase::GenerateCodeGenArgs(const CodeGenOptions &Opts,
   else
     GenerateArg(Consumer, OPT_fno_loop_interchange);
 
+  if (Opts.FuseLoops)
+    GenerateArg(Consumer, OPT_fexperimental_loop_fusion);
+  else
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MaskRay wrote:

If OPT_fno_experimental_loop_fusion  is not a cc1 option, the else branch will not be needed.

https://github.com/llvm/llvm-project/pull/142686