[WebAssembly] Add extra pattern for dot

llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td

@@ -1210,6 +1210,27 @@ defm EXTMUL_LOW_U :
 defm EXTMUL_HIGH_U :
   SIMDExtBinary<I64x2, extmul_high_u, "extmul_high_i32x4_u", 0xdf>;
 
+// Pattern for i32x4.dot_i16x8_s
+def : Pat<
+  (v4i32 (add
+    (wasm_shuffle
+      (v4i32 (extmul_low_s v8i16:$lhs, v8i16:$rhs)),
+      (v4i32 (extmul_high_s v8i16:$lhs, v8i16:$rhs)),
+      (i32 0), (i32 1), (i32 2), (i32 3),
+      (i32 8), (i32 9), (i32 10), (i32 11),
+      (i32 16), (i32 17), (i32 18), (i32 19),
+      (i32 24), (i32 25), (i32 26), (i32 27)),
+    (wasm_shuffle
+      (v4i32 (extmul_low_s v8i16:$lhs, v8i16:$rhs)),
+      (v4i32 (extmul_high_s v8i16:$lhs, v8i16:$rhs)),
+      (i32 4), (i32 5), (i32 6), (i32 7),
+      (i32 12), (i32 13), (i32 14), (i32 15),
+      (i32 20), (i32 21), (i32 22), (i32 23),
+      (i32 28), (i32 29), (i32 30), (i32 31)))
+  ),
+  (v4i32 (DOT v8i16:$lhs, v8i16:$rhs))
+>;
+
 //===----------------------------------------------------------------------===//
 // Floating-point unary arithmetic
 //===----------------------------------------------------------------------===//

llvm/test/CodeGen/WebAssembly/simd-dot-reductions.ll

@@ -0,0 +1,106 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc < %s -mattr=+simd128 | FileCheck %s
+
+target triple = "wasm32-unknown-unknown"
+
+define <4 x i32> @dot_sext_1(<8 x i16> %a, <8 x i16> %b) {
+; CHECK-LABEL: dot_sext_1:
+; CHECK:         .functype dot_sext_1 (v128, v128) -> (v128)
+; CHECK-NEXT:  # %bb.0:
+; CHECK-NEXT:    local.get 0
+; CHECK-NEXT:    local.get 1
+; CHECK-NEXT:    i32x4.dot_i16x8_s
+; CHECK-NEXT:    # fallthrough-return
+  %sext1 = sext <8 x i16> %a to <8 x i32>
+  %sext2 = sext <8 x i16> %b to <8 x i32>
+  %mul = mul <8 x i32> %sext1, %sext2
+  %shuffle1 = shufflevector <8 x i32> %mul, <8 x i32> poison, <4 x i32> <i32 0, i32 2, i32 4, i32 6>
+  %shuffle2 = shufflevector <8 x i32> %mul, <8 x i32> poison, <4 x i32> <i32 1, i32 3, i32 5, i32 7>
+  %res = add <4 x i32> %shuffle1, %shuffle2
+  ret <4 x i32> %res
+}
+
+
+define <4 x i32> @dot_sext_2(<8 x i16> %a, <8 x i16> %b) {
+; CHECK-LABEL: dot_sext_2:
+; CHECK:         .functype dot_sext_2 (v128, v128) -> (v128)
+; CHECK-NEXT:  # %bb.0:
+; CHECK-NEXT:    local.get 0
+; CHECK-NEXT:    local.get 1
+; CHECK-NEXT:    i32x4.dot_i16x8_s
+; CHECK-NEXT:    # fallthrough-return
+  %sext1 = sext <8 x i16> %a to <8 x i32>
+  %sext2 = sext <8 x i16> %b to <8 x i32>
+  %mul = mul <8 x i32> %sext1, %sext2
+  %shuffle1 = shufflevector <8 x i32> %mul, <8 x i32> poison, <4 x i32> <i32 0, i32 2, i32 4, i32 6>
+  %shuffle2 = shufflevector <8 x i32> %mul, <8 x i32> poison, <4 x i32> <i32 1, i32 3, i32 5, i32 7>
+  %res = add <4 x i32> %shuffle2, %shuffle1
+  ret <4 x i32> %res
+}
+
+define <4 x i32> @dot_sext_self(<8 x i16> %v) {
+; CHECK-LABEL: dot_sext_self:
+; CHECK:         .functype dot_sext_self (v128) -> (v128)
+; CHECK-NEXT:  # %bb.0:
+; CHECK-NEXT:    local.get 0
+; CHECK-NEXT:    local.get 0
+; CHECK-NEXT:    i32x4.dot_i16x8_s
+; CHECK-NEXT:    # fallthrough-return
+  %sext = sext <8 x i16> %v to <8 x i32>
+  %mul = mul <8 x i32> %sext, %sext
+  %shuffle1 = shufflevector <8 x i32> %mul, <8 x i32> poison, <4 x i32> <i32 0, i32 2, i32 4, i32 6>
+  %shuffle2 = shufflevector <8 x i32> %mul, <8 x i32> poison, <4 x i32> <i32 1, i32 3, i32 5, i32 7>
+  %res = add <4 x i32> %shuffle1, %shuffle2
+  ret <4 x i32> %res
+}
+
+; INFO: Negative test
+define <4 x i32> @dot_zext(<8 x i16> %a, <8 x i16> %b) {
+; CHECK-LABEL: dot_zext:
+; CHECK:         .functype dot_zext (v128, v128) -> (v128)
+; CHECK-NEXT:    .local v128
+; CHECK-NEXT:  # %bb.0:
+; CHECK-NEXT:    local.get 0
+; CHECK-NEXT:    local.get 1
+; CHECK-NEXT:    i32x4.extmul_low_i16x8_u
+; CHECK-NEXT:    local.tee 2
+; CHECK-NEXT:    local.get 0
+; CHECK-NEXT:    local.get 1
+; CHECK-NEXT:    i32x4.extmul_high_i16x8_u
+; CHECK-NEXT:    local.tee 1
+; CHECK-NEXT:    i8x16.shuffle 0, 1, 2, 3, 8, 9, 10, 11, 16, 17, 18, 19, 24, 25, 26, 27
+; CHECK-NEXT:    local.get 2
+; CHECK-NEXT:    local.get 1
+; CHECK-NEXT:    i8x16.shuffle 4, 5, 6, 7, 12, 13, 14, 15, 20, 21, 22, 23, 28, 29, 30, 31
+; CHECK-NEXT:    i32x4.add
+; CHECK-NEXT:    # fallthrough-return
+  %zext1 = zext <8 x i16> %a to <8 x i32>
+  %zext2 = zext <8 x i16> %b to <8 x i32>
+  %mul = mul <8 x i32> %zext1, %zext2
+  %shuffle1 = shufflevector <8 x i32> %mul, <8 x i32> poison, <4 x i32> <i32 0, i32 2, i32 4, i32 6>
+  %shuffle2 = shufflevector <8 x i32> %mul, <8 x i32> poison, <4 x i32> <i32 1, i32 3, i32 5, i32 7>
+  %res = add <4 x i32> %shuffle1, %shuffle2
+  ret <4 x i32> %res
+}
+
+; INFO: Negative test
+define <4 x i32> @dot_wrong_shuffle(<8 x i16> %a, <8 x i16> %b) {
+; CHECK-LABEL: dot_wrong_shuffle:
+; CHECK:         .functype dot_wrong_shuffle (v128, v128) -> (v128)
+; CHECK-NEXT:  # %bb.0:
+; CHECK-NEXT:    local.get 0
+; CHECK-NEXT:    local.get 1
+; CHECK-NEXT:    i32x4.extmul_low_i16x8_s
+; CHECK-NEXT:    local.get 0
+; CHECK-NEXT:    local.get 1
+; CHECK-NEXT:    i32x4.extmul_high_i16x8_s
+; CHECK-NEXT:    i32x4.add
+; CHECK-NEXT:    # fallthrough-return
+  %sext1 = sext <8 x i16> %a to <8 x i32>
+  %sext2 = sext <8 x i16> %b to <8 x i32>
+  %mul = mul <8 x i32> %sext1, %sext2
+  %shuffle1 = shufflevector <8 x i32> %mul, <8 x i32> poison, <4 x i32> <i32 0, i32 1, i32 2, i32 3>
+  %shuffle2 = shufflevector <8 x i32> %mul, <8 x i32> poison, <4 x i32> <i32 4, i32 5, i32 6, i32 7>
+  %res = add <4 x i32> %shuffle1, %shuffle2
+  ret <4 x i32> %res
+}