[clang] [CIR] Make cir.alloca alignment mandatory with default 0 (PR #172663)

[Andy Kaylor via cfe-commits]

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@@ -530,7 +530,7 @@ def CIR_AllocaOp : CIR_Op<"alloca", [
     StrAttr:$name,
     UnitAttr:$init,
     UnitAttr:$constant,
-    ConfinedAttr<OptionalAttr<I64Attr>, [IntMinValue<0>]>:$alignment,
+    ConfinedAttr<DefaultValuedAttr<I64Attr, "0">, [IntMinValue<0>]>:$alignment,
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andykaylor wrote:

Why do we need a default value at all? I thought we agreed that it was just going to be a required attribute, in which case the value would always be specified when the alloca is created.

https://github.com/llvm/llvm-project/pull/172663