[llvm] [NVPTX] Fix crash caused by ComputePTXValueVTs (PR #104524)

[Justin Fargnoli via llvm-commits]

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@@ -0,0 +1,45 @@
+; RUN: llc < %s -march=nvptx64 -mcpu=sm_20
+
+define <6 x half> @half6() {
+  ret <6 x half> zeroinitializer
+}
+
+define <10 x half> @half10() {
+  ret <10 x half> zeroinitializer
+}
+
+define <14 x half> @half14() {
+  ret <14 x half> zeroinitializer
+}
+
+define <18 x half> @half18() {
+  ret <18 x half> zeroinitializer
+}
+
+define <998 x half> @half998() {
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justinfargnoli wrote:

There isn't any particular significance to `998`. I just wanted to add a test case to prevent any special treatment that could occur. However, I didn't know that, "only the vectors up to 128bit in size have special treatment." In light of this, I've removed the tests. 

https://github.com/llvm/llvm-project/pull/104524