[llvm] [NVPTX] Change the alloca address space in NVPTXLowerAlloca (PR #154814)

[Alex MacLean via llvm-commits]

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@@ -139,21 +134,20 @@ define void @foo4() {
 ; PTX32-EMPTY:
 ; PTX32-NEXT:  // %bb.0:
 ; PTX32-NEXT:    mov.b32 %SPL, __local_depot3;
-; PTX32-NEXT:    cvta.local.u32 %SP, %SPL;
-; PTX32-NEXT:    add.u32 %r1, %SP, 0;
-; PTX32-NEXT:    add.u32 %r2, %SPL, 0;
-; PTX32-NEXT:    add.u32 %r3, %SP, 4;
-; PTX32-NEXT:    add.u32 %r4, %SPL, 4;
-; PTX32-NEXT:    st.local.b32 [%r2], 0;
-; PTX32-NEXT:    st.local.b32 [%r4], 0;
+; PTX32-NEXT:    add.u32 %r1, %SPL, 0;
+; PTX32-NEXT:    cvta.local.u32 %r2, %r1;
+; PTX32-NEXT:    add.u32 %r3, %SPL, 4;
+; PTX32-NEXT:    cvta.local.u32 %r4, %r3;
+; PTX32-NEXT:    st.local.b32 [%SPL], 0;
+; PTX32-NEXT:    st.local.b32 [%SPL+4], 0;
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AlexMaclean wrote:

This looks like a potential regression to me. We used to do one `cvta.local` while now we do two. 

https://github.com/llvm/llvm-project/pull/154814