[llvm] [InstSimplify][InstCombine] Remove unnecessary `m_c_*` matchers. (PR #81712)

[Nikita Popov via llvm-commits]

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@@ -3246,8 +3246,8 @@ static bool trySimplifyICmpWithAdds(CmpInst::Predicate Pred, Value *LHS,
 
   Value *X;
   const APInt *C1, *C2;
-  if (!match(LHS, m_c_Add(m_Value(X), m_APInt(C1))) ||
-      !match(RHS, m_c_Add(m_Specific(X), m_APInt(C2))))
+  if (!match(LHS, m_Add(m_Value(X), m_APInt(C1))) ||
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nikic wrote:

We only handle non-canonical patterns in InstSimplify if there is phase-ordering justification to do so, which is absent here. I did check the original review to confirm that this was done simply "because we can" and not for a specific reason.

https://github.com/llvm/llvm-project/pull/81712