[clang] [llvm] [RISCV][VLS] Support RISCV VLS calling convention (PR #100346)

[Craig Topper via cfe-commits]

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@@ -2206,6 +2206,21 @@ void Clang::AddRISCVTargetArgs(const ArgList &Args,
           << A->getSpelling() << Val;
     }
   }
+
+  if (Arg *A = Args.getLastArg(options::OPT_mriscv_abi_vlen_EQ)) {
+    StringRef ABIVLenStr = A->getValue();
+    unsigned ABIVLen;
+    const Driver &D = getToolChain().getDriver();
+    if (ABIVLenStr.getAsInteger(10, ABIVLen) || ABIVLen < 128 ||
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topperc wrote:

Why is 128? Doesn't the spec allow 32 and 64?

https://github.com/llvm/llvm-project/pull/100346