[llvm] [NVPTX] remove store.params of undef (PR #96940)

[Justin Lebar via llvm-commits]

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@@ -0,0 +1,93 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc < %s -march=nvptx64 | FileCheck %s
+; RUN: %if ptxas %{ llc < %s -march=nvptx64 | %ptxas-verify %}
+
+target triple = "nvptx64-nvidia-cuda"
+
+%struct.T = type { i64, <2 x i32>, <4 x i32> }
+
+declare void @test_call(%struct.T)
+
+define void @test_store_param_undef() {
+; CHECK-LABEL: test_store_param_undef(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<2>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    { // callseq 0, 0
+; CHECK-NEXT:    .param .align 16 .b8 param0[32];
+; CHECK-NEXT:    st.param.v2.b32 [param0+8], {%r1, 0};
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jlebar wrote:

I'm unclear on what this one is testing.  If the parameter is undef then why do we store into part of it?

https://github.com/llvm/llvm-project/pull/96940