[WebAssembly] Implement remaining relaxed SIMD instructions

Add codegen, intrinsics, and builtins for the i16x8.relaxed_q15mulr_s,
i16x8.dot_i8x16_i7x16_s, and i32x4.dot_i8x16_i7x16_add_s instructions. These are
the last instructions from the relaxed SIMD proposal[1] that had not been
implemented.

[1]:
https://github.com/WebAssembly/relaxed-simd/blob/main/proposals/relaxed-simd/Overview.md.

Differential Revision: https://reviews.llvm.org/D127170

clang/include/clang/Basic/BuiltinsWebAssembly.def

@@ -184,5 +184,10 @@ TARGET_BUILTIN(__builtin_wasm_relaxed_trunc_u_i32x4_f32x4, "V4UiV4f", "nc", "rel
 TARGET_BUILTIN(__builtin_wasm_relaxed_trunc_s_zero_i32x4_f64x2, "V4iV2d", "nc", "relaxed-simd")
 TARGET_BUILTIN(__builtin_wasm_relaxed_trunc_u_zero_i32x4_f64x2, "V4UiV2d", "nc", "relaxed-simd")
 
+TARGET_BUILTIN(__builtin_wasm_relaxed_q15mulr_s_i16x8, "V8sV8sV8s", "nc", "relaxed-simd")
+
+TARGET_BUILTIN(__builtin_wasm_dot_i8x16_i7x16_s_i16x8, "V8sV16ScV16Sc", "nc", "relaxed-simd")
+TARGET_BUILTIN(__builtin_wasm_dot_i8x16_i7x16_add_s_i32x4, "V4iV16ScV16ScV4i", "nc", "relaxed-simd")
+
 #undef BUILTIN
 #undef TARGET_BUILTIN

clang/lib/CodeGen/CGBuiltin.cpp

@@ -18684,6 +18684,26 @@ Value *CodeGenFunction::EmitWebAssemblyBuiltinExpr(unsigned BuiltinID,
     Function *Callee = CGM.getIntrinsic(IntNo);
     return Builder.CreateCall(Callee, {Vec});
   }
+  case WebAssembly::BI__builtin_wasm_relaxed_q15mulr_s_i16x8: {
+    Value *LHS = EmitScalarExpr(E->getArg(0));
+    Value *RHS = EmitScalarExpr(E->getArg(1));
+    Function *Callee = CGM.getIntrinsic(Intrinsic::wasm_relaxed_q15mulr_signed);
+    return Builder.CreateCall(Callee, {LHS, RHS});
+  }
+  case WebAssembly::BI__builtin_wasm_dot_i8x16_i7x16_s_i16x8: {
+    Value *LHS = EmitScalarExpr(E->getArg(0));
+    Value *RHS = EmitScalarExpr(E->getArg(1));
+    Function *Callee = CGM.getIntrinsic(Intrinsic::wasm_dot_i8x16_i7x16_signed);
+    return Builder.CreateCall(Callee, {LHS, RHS});
+  }
+  case WebAssembly::BI__builtin_wasm_dot_i8x16_i7x16_add_s_i32x4: {
+    Value *LHS = EmitScalarExpr(E->getArg(0));
+    Value *RHS = EmitScalarExpr(E->getArg(1));
+    Value *Acc = EmitScalarExpr(E->getArg(2));
+    Function *Callee =
+        CGM.getIntrinsic(Intrinsic::wasm_dot_i8x16_i7x16_add_signed);
+    return Builder.CreateCall(Callee, {LHS, RHS, Acc});
+  }
   default:
     return nullptr;
   }

clang/test/CodeGen/builtins-wasm.c

@@ -777,3 +777,24 @@ u32x4 relaxed_trunc_u_zero_i32x4_f64x2(f64x2 x) {
   // WEBASSEMBLY: call <4 x i32> @llvm.wasm.relaxed.trunc.unsigned.zero(<2 x double> %x)
   // WEBASSEMBLY-NEXT: ret
 }
+
+i16x8 relaxed_q15mulr_s_i16x8(i16x8 a, i16x8 b) {
+  return __builtin_wasm_relaxed_q15mulr_s_i16x8(a, b);
+  // WEBASSEMBLY: call <8 x i16> @llvm.wasm.relaxed.q15mulr.signed(
+  // WEBASSEMBLY-SAME: <8 x i16> %a, <8 x i16> %b)
+  // WEBASSEMBLY-NEXT: ret
+}
+
+i16x8 dot_i8x16_i7x16_s_i16x8(i8x16 a, i8x16 b) {
+  return __builtin_wasm_dot_i8x16_i7x16_s_i16x8(a, b);
+  // WEBASSEMBLY: call <8 x i16> @llvm.wasm.dot.i8x16.i7x16.signed(
+  // WEBASSEMBLY-SAME: <16 x i8> %a, <16 x i8> %b)
+  // WEBASSEMBLY-NEXT: ret
+}
+
+i32x4 dot_i8x16_i7x16_add_s_i32x4(i8x16 a, i8x16 b, i32x4 c) {
+  return __builtin_wasm_dot_i8x16_i7x16_add_s_i32x4(a, b, c);
+  // WEBASSEMBLY: call <4 x i32> @llvm.wasm.dot.i8x16.i7x16.add.signed(
+  // WEBASSEMBLY-SAME: <16 x i8> %a, <16 x i8> %b, <4 x i32> %c)
+  // WEBASSEMBLY-NEXT: ret
+}

llvm/include/llvm/IR/IntrinsicsWebAssembly.td

@@ -270,6 +270,20 @@ def int_wasm_relaxed_trunc_unsigned_zero:
             [llvm_v2f64_ty],
             [IntrNoMem, IntrSpeculatable]>;
 
+def int_wasm_relaxed_q15mulr_signed:
+  Intrinsic<[llvm_v8i16_ty],
+            [llvm_v8i16_ty, llvm_v8i16_ty],
+            [IntrNoMem, IntrSpeculatable]>;
+
+def int_wasm_dot_i8x16_i7x16_signed:
+  Intrinsic<[llvm_v8i16_ty],
+            [llvm_v16i8_ty, llvm_v16i8_ty],
+            [IntrNoMem, IntrSpeculatable]>;
+
+def int_wasm_dot_i8x16_i7x16_add_signed:
+  Intrinsic<[llvm_v4i32_ty],
+            [llvm_v16i8_ty, llvm_v16i8_ty, llvm_v4i32_ty],
+            [IntrNoMem, IntrSpeculatable]>;
 
 //===----------------------------------------------------------------------===//
 // Thread-local storage intrinsics

llvm/lib/Target/WebAssembly/WebAssemblyInstrSIMD.td

@@ -1403,7 +1403,6 @@ defm "" : SIMDLANESELECT<I16x8, 0x10a>;
 defm "" : SIMDLANESELECT<I32x4, 0x10b>;
 defm "" : SIMDLANESELECT<I64x2, 0x10c>;
 
-
 //===----------------------------------------------------------------------===//
 // Relaxed floating-point min and max.
 //===----------------------------------------------------------------------===//
@@ -1426,3 +1425,30 @@ defm SIMD_RELAXED_FMIN :
    RelaxedBinary<F64x2, int_wasm_relaxed_min, "relaxed_min", 0x10f>;
 defm SIMD_RELAXED_FMAX :
    RelaxedBinary<F64x2, int_wasm_relaxed_max, "relaxed_max", 0x110>;
+
+//===----------------------------------------------------------------------===//
+// Relaxed rounding q15 multiplication
+//===----------------------------------------------------------------------===//
+
+defm RELAXED_Q15MULR_S :
+  RelaxedBinary<I16x8, int_wasm_relaxed_q15mulr_signed, "relaxed_q15mulr_s",
+                0x111>;
+
+//===----------------------------------------------------------------------===//
+// Relaxed integer dot product
+//===----------------------------------------------------------------------===//
+
+defm RELAXED_DOT :
+  RELAXED_I<(outs V128:$dst), (ins V128:$lhs, V128:$rhs), (outs), (ins),
+            [(set (v8i16 V128:$dst), (int_wasm_dot_i8x16_i7x16_signed
+               (v16i8 V128:$lhs), (v16i8 V128:$rhs)))],
+            "i16x8.dot_i8x16_i7x16_s\t$dst, $lhs, $rhs",
+            "i16x8.dot_i8x16_i7x16_s", 0x112>;
+
+defm RELAXED_DOT_ADD :
+  RELAXED_I<(outs V128:$dst), (ins V128:$lhs, V128:$rhs, V128:$acc),
+            (outs), (ins),
+            [(set (v4i32 V128:$dst), (int_wasm_dot_i8x16_i7x16_add_signed
+               (v16i8 V128:$lhs), (v16i8 V128:$rhs), (v4i32 V128:$acc)))],
+            "i32x4.dot_i8x16_i7x16_add_s\t$dst, $lhs, $rhs, $acc",
+            "i32x4.dot_i8x16_i7x16_add_s", 0x113>;

llvm/test/CodeGen/WebAssembly/simd-intrinsics.ll

@@ -368,6 +368,30 @@ define <8 x i16> @laneselect_v8i16(<8 x i16> %a, <8 x i16> %b, <8 x i16> %c) {
   ret <8 x i16> %v
 }
 
+; CHECK-LABEL: relaxed_q15mulr_s_i16x8:
+; CHECK-NEXT: .functype relaxed_q15mulr_s_i16x8 (v128, v128) -> (v128){{$}}
+; CHECK-NEXT: i16x8.relaxed_q15mulr_s $push[[R:[0-9]+]]=, $0, $1{{$}}
+; CHECK-NEXT: return $pop[[R]]{{$}}
+declare <8 x i16> @llvm.wasm.relaxed.q15mulr.signed(<8 x i16>, <8 x i16>)
+define <8 x i16> @relaxed_q15mulr_s_i16x8(<8 x i16> %a, <8 x i16> %b) {
+  %v = call <8 x i16> @llvm.wasm.relaxed.q15mulr.signed(
+    <8 x i16> %a, <8 x i16> %b
+  )
+  ret <8 x i16> %v
+}
+
+; CHECK-LABEL: dot_i8x16_i7x16_s_i16x8:
+; CHECK-NEXT: .functype dot_i8x16_i7x16_s_i16x8 (v128, v128) -> (v128){{$}}
+; CHECK-NEXT: i16x8.dot_i8x16_i7x16_s $push[[R:[0-9]+]]=, $0, $1{{$}}
+; CHECK-NEXT: return $pop[[R]]{{$}}
+declare <8 x i16> @llvm.wasm.dot.i8x16.i7x16.signed(<16 x i8>, <16 x i8>)
+define <8 x i16> @dot_i8x16_i7x16_s_i16x8(<16 x i8> %a, <16 x i8> %b) {
+  %v = call <8 x i16> @llvm.wasm.dot.i8x16.i7x16.signed(
+    <16 x i8> %a, <16 x i8> %b
+  )
+  ret <8 x i16> %v
+}
+
 ; ==============================================================================
 ; 4 x i32
 ; ==============================================================================
@@ -568,6 +592,20 @@ define <4 x i32> @relaxed_trunc_u_zero(<2 x double> %x) {
   ret <4 x i32> %a
 }
 
+; CHECK-LABEL: dot_i8x16_i7x16_add_s_i32x4:
+; CHECK-NEXT: .functype dot_i8x16_i7x16_add_s_i32x4 (v128, v128, v128) -> (v128){{$}}
+; CHECK-NEXT: i32x4.dot_i8x16_i7x16_add_s $push[[R:[0-9]+]]=, $0, $1, $2{{$}}
+; CHECK-NEXT: return $pop[[R]]{{$}}
+declare <4 x i32> @llvm.wasm.dot.i8x16.i7x16.add.signed(<16 x i8>, <16 x i8>,
+                                                        <4 x i32>)
+define <4 x i32> @dot_i8x16_i7x16_add_s_i32x4(<16 x i8> %a, <16 x i8> %b,
+                                              <4 x i32> %c) {
+  %v = call <4 x i32> @llvm.wasm.dot.i8x16.i7x16.add.signed(
+    <16 x i8> %a, <16 x i8> %b, <4 x i32> %c
+  )
+  ret <4 x i32> %v
+}
+
 ; ==============================================================================
 ; 2 x i64
 ; ==============================================================================

llvm/test/MC/WebAssembly/simd-encodings.s

@@ -830,8 +830,13 @@ main:
     # CHECK: f64x2.relaxed_max # encoding: [0xfd,0x90,0x02]
     f64x2.relaxed_max
 
-    # TODO: i16x8.relaxed_q15mulr_s # encoding: [0xfd,0x91,0x02]
-    # TODO: i16x8.dot_i8x16_i7x16_s # encoding: [0xfd,0x92,0x02]
-    # TODO: i32x4.dot_i8x16_i7x16_add_s # encoding: [0xfd,0x93,0x02]
+    # CHECK: i16x8.relaxed_q15mulr_s # encoding: [0xfd,0x91,0x02]
+    i16x8.relaxed_q15mulr_s
+
+    # CHECK: i16x8.dot_i8x16_i7x16_s # encoding: [0xfd,0x92,0x02]
+    i16x8.dot_i8x16_i7x16_s
+
+    # CHECK: i32x4.dot_i8x16_i7x16_add_s # encoding: [0xfd,0x93,0x02]
+    i32x4.dot_i8x16_i7x16_add_s
 
     end_function