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

[Kito Cheng via llvm-commits]

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@@ -111,9 +115,51 @@ void RISCVABIInfo::appendAttributeMangling(StringRef AttrStr,
 }
 
 void RISCVABIInfo::computeInfo(CGFunctionInfo &FI) const {
+  unsigned ABIVLen;
+  switch (FI.getExtInfo().getCC()) {
+  default:
+    ABIVLen = 1;
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kito-cheng wrote:

Always use ABIVLen = 0 to represent it's disabled? I saw some other place use 0, but here use 1, which introduce magic constant, and also inconsistent 

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