[llvm] [mlir] [MLIR][NVVM] Add globaltimer_lo support in NVVM Dialect and NVPTX backend (PR #154672)

[via llvm-commits]

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@@ -4358,10 +4358,12 @@ let hasSideEffects = 1 in {
   def SREG_CLOCK : PTX_READ_SREG_R32<"clock", int_nvvm_read_ptx_sreg_clock>;
   def SREG_CLOCK64 : PTX_READ_SREG_R64<"clock64", int_nvvm_read_ptx_sreg_clock64>;
   def SREG_GLOBALTIMER : PTX_READ_SREG_R64<"globaltimer", int_nvvm_read_ptx_sreg_globaltimer>;
+  def SREG_GLOBALTIMER_LO : PTX_READ_SREG_R32<"globaltimer_lo", int_nvvm_read_ptx_sreg_globaltimer_lo>;
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gonzalobg wrote:

Since `globaltimer` exposes the 64-bit, `globaltimer_lo` doesn't hold any significance either as far as I can tell: just `trunc` the result of globaltimer to an i32 and you get `_lo`.

https://github.com/llvm/llvm-project/pull/154672