[llvm] [GlobalISel] Make sure to check for load barriers when merging G_EXTRACT_VECTOR_ELT into G_LOAD. (PR #82306)

[Jessica Paquette via llvm-commits]

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@@ -0,0 +1,91 @@
+# RUN: llc -run-pass=aarch64-prelegalizer-combiner %s -o - | FileCheck %s
+
+--- |
+  ; ModuleID = 'in.ll'
+  source_filename = "in.ll"
+  target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128"
+  
+  define i32 @f(ptr %0) {
+    %2 = load <2 x i32>, ptr %0, align 8
+    store <4 x i32> zeroinitializer, ptr %0, align 16
+    %3 = extractelement <2 x i32> %2, i64 0
+    ret i32 %3
+  }
+
+...
+---
+name:            f
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ornata wrote:

-simplify-mir?

https://github.com/llvm/llvm-project/pull/82306