[clang] [llvm] [WebAssembly] Add `-i128:128` to the `datalayout` string. (PR #119204)

[Derek Schuff via llvm-commits]

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@@ -524,9 +524,7 @@ define i64 @utest_f64i64(double %x) {
 ; CHECK-NEXT:    local.get 0
 ; CHECK-NEXT:    call __fixunsdfti
 ; CHECK-NEXT:    local.get 1
-; CHECK-NEXT:    i32.const 8
-; CHECK-NEXT:    i32.add
-; CHECK-NEXT:    i64.load 0
+; CHECK-NEXT:    i64.load 8
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dschuff wrote:

I'm curious why these layout changes lead to extra folding here, since the alignment of i128 previously matched the alignment for i64 and these are i64 loads... actually I also don't know why the alignment should affect folding anyway. Are we missing a folding opportunity somewhere else too? 

https://github.com/llvm/llvm-project/pull/119204