[clang] [llvm] [CUDA] Add a pseudo GPU sm_next which allows overriding for SM/PTX version. (PR #100247)

[Justin Holewinski via cfe-commits]

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@@ -26,24 +27,38 @@ static cl::opt<bool>
     NoF16Math("nvptx-no-f16-math", cl::Hidden,
               cl::desc("NVPTX Specific: Disable generation of f16 math ops."),
               cl::init(false));
+static cl::opt<unsigned>
+    NextSM("nvptx-next-sm", cl::Hidden,
+           cl::desc("NVPTX Specific: Override SM ID for sm_next."),
+           cl::init(90));
+static cl::opt<unsigned>
+    NextPTX("nvptx-next-ptx", cl::Hidden,
+            cl::desc("NVPTX Specific: Override PTX version for sm_next."),
+            cl::init(85));
+
 // Pin the vtable to this file.
 void NVPTXSubtarget::anchor() {}
 
 NVPTXSubtarget &NVPTXSubtarget::initializeSubtargetDependencies(StringRef CPU,
                                                                 StringRef FS) {
-    // Provide the default CPU if we don't have one.
-    TargetName = std::string(CPU.empty() ? "sm_30" : CPU);
+  // Provide the default CPU if we don't have one.
+  TargetName = std::string(CPU.empty() ? "sm_30" : CPU);
 
-    ParseSubtargetFeatures(TargetName, /*TuneCPU*/ TargetName, FS);
+  ParseSubtargetFeatures(TargetName, /*TuneCPU*/ TargetName, FS);
+  if (TargetName == "sm_next") {
+    TargetName = "sm_" + itostr(NextSM);
+    FullSmVersion = NextSM * 10;
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jholewinski wrote:

It would be good to support architecture conditional targets, e.g. `sm_90a`, with this feature.

https://github.com/llvm/llvm-project/pull/100247