[ARM,MVE] Fix valid immediate range for vsliq_n.

In common with most MVE immediate shift instructions, the left shift
takes an immediate in the range [0,n-1], while the right shift takes
one in the range [1,n]. I had absent-mindedly made them both the
latter.

While I'm here, I've added a set of regression tests checking both
ends of the immediate range for a representative sample of the
immediate shifts.

clang/include/clang/Basic/arm_mve.td

@@ -684,7 +684,7 @@ let params = [s16, s32], pnt = PNT_NType in {
   defm vqrshrun : VSHRN<UHalfVector, imm_1toHalfN, (? 1,0,1,0)>;
 }
 let params = T.Int, pnt = PNT_NType in {
-  defm vsli : DyadicImmShift<Vector, imm_1toN>;
+  defm vsli : DyadicImmShift<Vector, imm_0toNm1>;
   defm vsri : DyadicImmShift<Vector, imm_1toN>;
 }
 

clang/test/Sema/arm-mve-immediates.c

@@ -110,3 +110,96 @@ void test_lane_indices(uint8x16_t v16, uint16x8_t v8,
   vsetq_lane_u64(23, v2, 1);
   vsetq_lane_u64(23, v2, 2); // expected-error {{argument value 2 is outside the valid range [0, 1]}}
 }
+
+void test_immediate_shifts(uint8x16_t vb, uint16x8_t vh, uint32x4_t vw)
+{
+  vshlq_n(vb, 0);
+  vshlq_n(vb, 7);
+  vshlq_n(vh, 0);
+  vshlq_n(vh, 15);
+  vshlq_n(vw, 0);
+  vshlq_n(vw, 31);
+
+  vshlq_n(vb, -1); // expected-error {{argument value -1 is outside the valid range [0, 7]}}
+  vshlq_n(vb, 8); // expected-error {{argument value 8 is outside the valid range [0, 7]}}
+  vshlq_n(vh, -1); // expected-error {{argument value -1 is outside the valid range [0, 15]}}
+  vshlq_n(vh, 16); // expected-error {{argument value 16 is outside the valid range [0, 15]}}
+  vshlq_n(vw, -1); // expected-error {{argument value -1 is outside the valid range [0, 31]}}
+  vshlq_n(vw, 32); // expected-error {{argument value 32 is outside the valid range [0, 31]}}
+
+  vqshlq_n(vb, 0);
+  vqshlq_n(vb, 7);
+  vqshlq_n(vh, 0);
+  vqshlq_n(vh, 15);
+  vqshlq_n(vw, 0);
+  vqshlq_n(vw, 31);
+
+  vqshlq_n(vb, -1); // expected-error {{argument value -1 is outside the valid range [0, 7]}}
+  vqshlq_n(vb, 8); // expected-error {{argument value 8 is outside the valid range [0, 7]}}
+  vqshlq_n(vh, -1); // expected-error {{argument value -1 is outside the valid range [0, 15]}}
+  vqshlq_n(vh, 16); // expected-error {{argument value 16 is outside the valid range [0, 15]}}
+  vqshlq_n(vw, -1); // expected-error {{argument value -1 is outside the valid range [0, 31]}}
+  vqshlq_n(vw, 32); // expected-error {{argument value 32 is outside the valid range [0, 31]}}
+
+  vsliq(vb, vb, 0);
+  vsliq(vb, vb, 7);
+  vsliq(vh, vh, 0);
+  vsliq(vh, vh, 15);
+  vsliq(vw, vw, 0);
+  vsliq(vw, vw, 31);
+
+  vsliq(vb, vb, -1); // expected-error {{argument value -1 is outside the valid range [0, 7]}}
+  vsliq(vb, vb, 8); // expected-error {{argument value 8 is outside the valid range [0, 7]}}
+  vsliq(vh, vh, -1); // expected-error {{argument value -1 is outside the valid range [0, 15]}}
+  vsliq(vh, vh, 16); // expected-error {{argument value 16 is outside the valid range [0, 15]}}
+  vsliq(vw, vw, -1); // expected-error {{argument value -1 is outside the valid range [0, 31]}}
+  vsliq(vw, vw, 32); // expected-error {{argument value 32 is outside the valid range [0, 31]}}
+
+  vshllbq(vb, 1);
+  vshllbq(vb, 8);
+  vshllbq(vh, 1);
+  vshllbq(vh, 16);
+
+  vshllbq(vb, 0); // expected-error {{argument value 0 is outside the valid range [1, 8]}}
+  vshllbq(vb, 9); // expected-error {{argument value 9 is outside the valid range [1, 8]}}
+  vshllbq(vh, 0); // expected-error {{argument value 0 is outside the valid range [1, 16]}}
+  vshllbq(vh, 17); // expected-error {{argument value 17 is outside the valid range [1, 16]}}
+
+  vshrq(vb, 1);
+  vshrq(vb, 8);
+  vshrq(vh, 1);
+  vshrq(vh, 16);
+  vshrq(vw, 1);
+  vshrq(vw, 32);
+
+  vshrq(vb, 0); // expected-error {{argument value 0 is outside the valid range [1, 8]}}
+  vshrq(vb, 9); // expected-error {{argument value 9 is outside the valid range [1, 8]}}
+  vshrq(vh, 0); // expected-error {{argument value 0 is outside the valid range [1, 16]}}
+  vshrq(vh, 17); // expected-error {{argument value 17 is outside the valid range [1, 16]}}
+  vshrq(vw, 0); // expected-error {{argument value 0 is outside the valid range [1, 32]}}
+  vshrq(vw, 33); // expected-error {{argument value 33 is outside the valid range [1, 32]}}
+
+  vshrntq(vb, vh, 1);
+  vshrntq(vb, vh, 8);
+  vshrntq(vh, vw, 1);
+  vshrntq(vh, vw, 16);
+
+  vshrntq(vb, vh, 0); // expected-error {{argument value 0 is outside the valid range [1, 8]}}
+  vshrntq(vb, vh, 9); // expected-error {{argument value 9 is outside the valid range [1, 8]}}
+  vshrntq(vh, vw, 0); // expected-error {{argument value 0 is outside the valid range [1, 16]}}
+  vshrntq(vh, vw, 17); // expected-error {{argument value 17 is outside the valid range [1, 16]}}
+
+  vsriq(vb, vb, 1);
+  vsriq(vb, vb, 8);
+  vsriq(vh, vh, 1);
+  vsriq(vh, vh, 16);
+  vsriq(vw, vw, 1);
+  vsriq(vw, vw, 32);
+
+  vsriq(vb, vb, 0); // expected-error {{argument value 0 is outside the valid range [1, 8]}}
+  vsriq(vb, vb, 9); // expected-error {{argument value 9 is outside the valid range [1, 8]}}
+  vsriq(vh, vh, 0); // expected-error {{argument value 0 is outside the valid range [1, 16]}}
+  vsriq(vh, vh, 17); // expected-error {{argument value 17 is outside the valid range [1, 16]}}
+  vsriq(vw, vw, 0); // expected-error {{argument value 0 is outside the valid range [1, 32]}}
+  vsriq(vw, vw, 33); // expected-error {{argument value 33 is outside the valid range [1, 32]}}
+}