[clang] [Clang][RISCV] Add vcreate intrinsics for RVV non-tuple types (PR #70355)

[Wang Pengcheng via cfe-commits]

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@@ -345,6 +345,54 @@ class VString<int nf, bit signed> {
                    !eq(nf, 8): !if(signed, "vvvvvvvv", "UvUvUvUvUvUvUvUv"));
 }
 
+
+class FixedVString<int fixed_lmul, int num, bit signed> {
+  string V = "(LFixedLog2LMUL:" # fixed_lmul # ")" # !if(signed, "v", "Uv");
+  string S = !cond(!eq(num, 1): V,
+                   !eq(num, 2): V # V,
+                   !eq(num, 4): V # V # V # V,
+                   !eq(num, 8): V # V # V # V # V # V # V # V,
+                   true: "");
+}
+
+// This function is used in RVVNonTupleVCreateBuiltin to determine how many
+// variable we need to assemble the bigger LMUL value.
+// X = 2^{pow_x - pow_y}, with value range of pow_x, pow_y = [0, 3], pow_x > pow_y
+class GetPowDiff<int pow_x, int pow_y> {
+  int X = !cond(!eq(pow_x, 1): 2,
+                !eq(pow_x, 2):
+                  !cond(!eq(pow_y, 0): 4,
+                        !eq(pow_y, 1): 2,
+                        true: 0),
+                !eq(pow_x, 3):
+                  !cond(!eq(pow_y, 0): 8,
+                        !eq(pow_y, 1): 4,
+                        !eq(pow_y, 2): 2,
+                        true: 0),
+                true: 0);
+}
+
+multiclass RVVNonTupleVCreateBuiltin<int dst_lmul, list<int> src_lmul_list> {
+  defvar dst_v = FixedVString<dst_lmul, 1, /*signed=*/true>.V;
+  defvar dst_uv = FixedVString<dst_lmul, 1, /*signed=*/false>.V;
+  foreach src_lmul = src_lmul_list in {
+    defvar num = GetPowDiff<dst_lmul, src_lmul>.X;
+
+    defvar src_v = FixedVString<src_lmul, num, /*signed=*/true>.V;
+    defvar src_s = FixedVString<src_lmul, num, /*signed=*/true>.S;
+
+    def vcreate # src_v # dst_v : RVVBuiltin<src_v # dst_v,
+                                              dst_v # src_s,
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wangpc-pp wrote:

The indent is not correct.

https://github.com/llvm/llvm-project/pull/70355