[llvm] [PowerPC][RFC] Retire PPCExpandISel pass (PR #84289)

[Chen Zheng via llvm-commits]

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@@ -32,14 +32,7 @@ STATISTIC(NumExpanded, "Number of ISEL instructions expanded");
 STATISTIC(NumRemoved, "Number of ISEL instructions removed");
 STATISTIC(NumFolded, "Number of ISEL instructions folded");
 
-// If -ppc-gen-isel=false is set, we will disable generating the ISEL
-// instruction on all PPC targets. Otherwise, if the user set option
-// -misel or the platform supports ISEL by default, still generate the
-// ISEL instruction, else expand it.
-static cl::opt<bool>
-    GenerateISEL("ppc-gen-isel",
-                 cl::desc("Enable generating the ISEL instruction."),
-                 cl::init(true), cl::Hidden);
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chenzheng1030 wrote:

As a first step, why not just set the default value to false here?

If we don't get any regressions, then as a follow up, we can remove the pass?

https://github.com/llvm/llvm-project/pull/84289