PPC: [wasm-simd] Implement S128Const and S128AllOnes

Change-Id: I8f8b0b525541cec1a814b7df6ffe0baf00514929
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2554526Reviewed-by: Junliang Yan <junyan@redhat.com>
Commit-Queue: Milad Fa <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/master@{#71344}

src/compiler/backend/ppc/code-generator-ppc.cc

@@ -2892,11 +2892,28 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
       __ vxor(dst, i.InputSimd128Register(0), src);
       break;
     }
+    case kPPC_S128Const: {
+      Simd128Register dst = i.OutputSimd128Register();
+      constexpr int lane_width_in_bytes = 8;
+      uint64_t low = make_uint64(i.InputUint32(1), i.InputUint32(0));
+      uint64_t high = make_uint64(i.InputUint32(3), i.InputUint32(2));
+      __ mov(r0, Operand(low));
+      __ mov(ip, Operand(high));
+      __ mtvsrd(dst, ip);
+      __ mtvsrd(kScratchDoubleReg, r0);
+      __ vinsertd(dst, kScratchDoubleReg, Operand(1 * lane_width_in_bytes));
+      break;
+    }
     case kPPC_S128Zero: {
       Simd128Register dst = i.OutputSimd128Register();
       __ vxor(dst, dst, dst);
       break;
     }
+    case kPPC_S128AllOnes: {
+      Simd128Register dst = i.OutputSimd128Register();
+      __ vcmpequb(dst, dst, dst);
+      break;
+    }
     case kPPC_S128Not: {
       Simd128Register dst = i.OutputSimd128Register();
       Simd128Register src = i.InputSimd128Register(0);

src/compiler/backend/ppc/instruction-codes-ppc.h

@@ -373,7 +373,9 @@ namespace compiler {
   V(PPC_S128And)                     \
   V(PPC_S128Or)                      \
   V(PPC_S128Xor)                     \
+  V(PPC_S128Const)                   \
   V(PPC_S128Zero)                    \
+  V(PPC_S128AllOnes)                 \
   V(PPC_S128Not)                     \
   V(PPC_S128Select)                  \
   V(PPC_S128AndNot)                  \

src/compiler/backend/ppc/instruction-scheduler-ppc.cc

@@ -296,7 +296,9 @@ int InstructionScheduler::GetTargetInstructionFlags(
     case kPPC_S128And:
     case kPPC_S128Or:
     case kPPC_S128Xor:
+    case kPPC_S128Const:
     case kPPC_S128Zero:
+    case kPPC_S128AllOnes:
     case kPPC_S128Not:
     case kPPC_S128Select:
     case kPPC_S128AndNot:

src/compiler/backend/ppc/instruction-selector-ppc.cc

@@ -2439,7 +2439,24 @@ void InstructionSelector::VisitS128Select(Node* node) {
        g.UseRegister(node->InputAt(2)));
 }
 
-void InstructionSelector::VisitS128Const(Node* node) { UNIMPLEMENTED(); }
+void InstructionSelector::VisitS128Const(Node* node) {
+  PPCOperandGenerator g(this);
+  uint32_t val[kSimd128Size / sizeof(uint32_t)];
+  base::Memcpy(val, S128ImmediateParameterOf(node->op()).data(), kSimd128Size);
+  // If all bytes are zeros, avoid emitting code for generic constants.
+  bool all_zeros = !(val[0] || val[1] || val[2] || val[3]);
+  bool all_ones = val[0] == UINT32_MAX && val[1] == UINT32_MAX &&
+                  val[2] == UINT32_MAX && val[3] == UINT32_MAX;
+  InstructionOperand dst = g.DefineAsRegister(node);
+  if (all_zeros) {
+    Emit(kPPC_S128Zero, dst);
+  } else if (all_ones) {
+    Emit(kPPC_S128AllOnes, dst);
+  } else {
+    Emit(kPPC_S128Const, dst, g.UseImmediate(val[0]), g.UseImmediate(val[1]),
+         g.UseImmediate(val[2]), g.UseImmediate(val[3]));
+  }
+}
 
 void InstructionSelector::EmitPrepareResults(
     ZoneVector<PushParameter>* results, const CallDescriptor* call_descriptor,