[llvm] [NVPTX] Implement `isTruncateFree(EVT FromVT, EVT ToVT)` (PR #138605)

[Kevin McAfee via llvm-commits]

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@@ -155,11 +155,19 @@ class NVPTXTargetLowering : public TargetLowering {
                              Instruction *I = nullptr) const override;
 
   bool isTruncateFree(Type *SrcTy, Type *DstTy) const override {
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kalxr wrote:

Seems like Hexagon is the only target that does it this way, but seems simpler:
 https://github.com/llvm/llvm-project/blob/1c1238d3615a7e1a99570d1e02de3b538d2e0669/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp#L2145

https://github.com/llvm/llvm-project/pull/138605