PPC: [wasm] Int64Lowering of Int64Mul.

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

Index: src/compiler/ppc/code-generator-ppc.cc
diff --git a/src/compiler/ppc/code-generator-ppc.cc b/src/compiler/ppc/code-generator-ppc.cc
index d827dead815eca3e4691160460dcca76fbc8a2a6..88e47b4ea6967d9f46ce2a9f6cb6a2e4e4d188fc 100644
--- a/src/compiler/ppc/code-generator-ppc.cc
+++ b/src/compiler/ppc/code-generator-ppc.cc
@@ -991,6 +991,18 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
       __ sube(i.OutputRegister(1), i.InputRegister(1), i.InputRegister(3));
       DCHECK_EQ(LeaveRC, i.OutputRCBit());
       break;
+    case kPPC_MulPair:
+      // i.InputRegister(0) ... left low word.
+      // i.InputRegister(1) ... left high word.
+      // i.InputRegister(2) ... right low word.
+      // i.InputRegister(3) ... right high word.
+      __ mullw(i.TempRegister(0), i.InputRegister(0), i.InputRegister(3));
+      __ mullw(i.TempRegister(1), i.InputRegister(2), i.InputRegister(1));
+      __ add(i.TempRegister(0), i.TempRegister(0), i.TempRegister(1));
+      __ mullw(i.OutputRegister(0), i.InputRegister(0), i.InputRegister(2));
+      __ mulhwu(i.OutputRegister(1), i.InputRegister(0), i.InputRegister(2));
+      __ add(i.OutputRegister(1), i.OutputRegister(1), i.TempRegister(0));
+      break;
     case kPPC_ShiftLeftPair:
       if (instr->InputAt(2)->IsImmediate()) {
         __ ShiftLeftPair(i.OutputRegister(0), i.OutputRegister(1),