LLVM 23: Adapt codegen test to moved assume

[TimNN]

I wasn't completely sure what the important part of this test is - based on the "Make sure we don't create br or select instructions" comment I assume it's that the load is followed ~immediately by the ret, and that the presence or absence of the assume doesn't really matter (it's been moved up a few lines to before the load):

; Function Attrs
define noundef i32 @foo(ptr noalias nofree noundef align 8 captures(none) dereferenceable(16) %x) unnamed_addr #0 { 
start
 %_6 = load ptr, ptr %x, align 8, !nonnull !4, !noundef !4 
 %0 = getelementptr inbounds nuw i8, ptr %x, i64 8 
 %_7 = load ptr, ptr %0, align 8, !nonnull !4, !noundef !4 
 %_8 = icmp ne ptr %_6, %_7 
 tail call void @llvm.assume(i1 %_8) 
 %_14 = getelementptr inbounds nuw i8, ptr %_6, i64 4 
 store ptr %_14, ptr %x, align 8 
 %_4 = load i32, ptr %_6, align 4, !noundef !4 
 ret i32 %_4 
} 

(If you have a suggestion for how to adapt the test without introducing revisions, I'd be happy to do so).

@rustbot label llvm-main

original CI failure

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r? @mu001999

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[mu001999]

r? dianqk (creator of this test)

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[dianqk]

I think these checks can be changed to something like:

// CHECK: [[INNER:%.*]] = load ptr, ptr %x
// CHECK: [[RET:%.*]] = load i32, ptr [[INNER]]

You can remove or add more CHECK-NOT br or CHECK-NOT select.

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