[clang-tools-extra] [libcxx] [clang] [libc] [compiler-rt] [flang] [llvm] [Clang] Generate the GEP instead of adding AST nodes (PR #73730)

[Bill Wendling via cfe-commits]

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@@ -4022,8 +4169,36 @@ LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
       ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
     else
       ArrayLV = EmitLValue(Array);
+
     auto *Idx = EmitIdxAfterBase(/*Promote*/true);
 
+    if (SanOpts.has(SanitizerKind::ArrayBounds)) {
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bwendling wrote:

@rapidsna It would ignore that case, because it could have side-effects. But if it's the base pointer, it could be reused. I added a method in the visitor. I quickly tried the `CodeGenFunction::EmitLValueForField` method. Does it work with fields that aren't at the top level? At first glance, it doesn't appear to do that.

@efriedma-quic Okay. I changed it to look through the GEPs for the base pointer.

https://github.com/llvm/llvm-project/pull/73730