[llvm] [NVPTX] Lower allocas to the local address space (PR #204346)

[Tim Besard via llvm-commits]

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@@ -21,18 +21,17 @@ define internal i32 @foo() {
 ; CHECK-NEXT:  prototype_0 : .callprototype (.param .b32 _) _ (.param .align 1 .b8 _[1], .param .b64 _);
 ; CHECK-NEXT:  // %bb.0: // %entry
 ; CHECK-NEXT:    mov.b64 %SPL, __local_depot0;
-; CHECK-NEXT:    cvta.local.u64 %SP, %SPL;
-; CHECK-NEXT:    ld.global.b64 %rd1, [ptr];
+; CHECK-NEXT:    add.u64 %rd1, %SPL, 0;
+; CHECK-NEXT:    cvta.local.u64 %rd2, %rd1;
+; CHECK-NEXT:    ld.global.b64 %rd3, [ptr];
 ; CHECK-NEXT:    { // callseq 0, 0
 ; CHECK-NEXT:    .param .align 1 .b8 param0[1];
 ; CHECK-NEXT:    .param .b64 param1;
 ; CHECK-NEXT:    .param .b32 retval0;
-; CHECK-NEXT:    add.u64 %rd2, %SP, 0;
 ; CHECK-NEXT:    st.param.b64 [param1], %rd2;
-; CHECK-NEXT:    add.u64 %rd3, %SPL, 1;
-; CHECK-NEXT:    ld.local.b8 %rs1, [%rd3];
+; CHECK-NEXT:    ld.b8 %rs1, [%SPL+1];
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maleadt wrote:

> It may be interesting to add an optimized llc run to verify that AS inference still can do its job in the optimized build.

Doesn't `llc` in here default to `-O2` already? I'll make it explicit though.

https://github.com/llvm/llvm-project/pull/204346