PPC/s390: [wasm-simd] Use S128AllOnes in v128.const implementation

Change-Id: I997abb5576224d4e7fe00ef593afa0265ef80e16
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2288428Reviewed-by: Junliang Yan <jyan@ca.ibm.com>
Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#68747}

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

@@ -2330,6 +2330,8 @@ void InstructionSelector::VisitS128Select(Node* node) {
        g.UseRegister(node->InputAt(2)));
 }
 
+void InstructionSelector::VisitS128Const(Node* node) { UNIMPLEMENTED(); }
+
 void InstructionSelector::VisitI16x8AddSaturateS(Node* node) {
   UNIMPLEMENTED();
 }

src/compiler/backend/s390/code-generator-s390.cc

@@ -3938,6 +3938,11 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
       __ vx(dst, dst, dst, Condition(0), Condition(0), Condition(0));
       break;
     }
+    case kS390_S128AllOnes: {
+      Simd128Register dst = i.OutputSimd128Register();
+      __ vceq(dst, dst, dst, Condition(0), Condition(3));
+      break;
+    }
     case kS390_S128Select: {
       Simd128Register dst = i.OutputSimd128Register();
       Simd128Register mask = i.InputSimd128Register(0);

src/compiler/backend/s390/instruction-codes-s390.h

@@ -380,6 +380,7 @@ namespace compiler {
   V(S390_S128Xor)                           \
   V(S390_S128Const)                         \
   V(S390_S128Zero)                          \
+  V(S390_S128AllOnes)                       \
   V(S390_S128Not)                           \
   V(S390_S128Select)                        \
   V(S390_S128AndNot)                        \

src/compiler/backend/s390/instruction-scheduler-s390.cc

@@ -326,6 +326,7 @@ int InstructionScheduler::GetTargetInstructionFlags(
     case kS390_S128Xor:
     case kS390_S128Const:
     case kS390_S128Zero:
+    case kS390_S128AllOnes:
     case kS390_S128Not:
     case kS390_S128Select:
     case kS390_S128AndNot:

src/compiler/backend/s390/instruction-selector-s390.cc

@@ -2878,15 +2878,17 @@ void InstructionSelector::VisitS8x16Swizzle(Node* node) {
 
 void InstructionSelector::VisitS128Const(Node* node) {
   S390OperandGenerator g(this);
-  static const int kUint32Immediates = 4;
-  uint32_t val[kUint32Immediates];
-  STATIC_ASSERT(sizeof(val) == kSimd128Size);
+  uint32_t val[kSimd128Size / sizeof(uint32_t)];
   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]);
+  // 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(kS390_S128Zero, dst);
+  } else if (all_ones) {
+    Emit(kS390_S128AllOnes, dst);
   } else {
     // We have to use Pack4Lanes to reverse the bytes (lanes) on BE,
     // Which in this case is ineffective on LE.