MIPS64: Fix code generator and simulator for DEXTM.

src/compiler/mips64/code-generator-mips64.cc

Index: src/compiler/mips64/code-generator-mips64.cc
diff --git a/src/compiler/mips64/code-generator-mips64.cc b/src/compiler/mips64/code-generator-mips64.cc
index f9bc68eb74750abbcb55a4a31565708c54207f06..4f1c59869e5cb7ebc6cf984a9b34b199ad8530dd 100644
--- a/src/compiler/mips64/code-generator-mips64.cc
+++ b/src/compiler/mips64/code-generator-mips64.cc
@@ -1221,7 +1221,7 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
       if (size > 0 && size <= 32 && pos >= 0 && pos < 32) {
         __ Dext(i.OutputRegister(), i.InputRegister(0), i.InputInt8(1),
                 i.InputInt8(2));
-      } else if (size > 32 && size <= 64 && pos > 0 && pos < 32) {
+      } else if (size > 32 && size <= 64 && pos >= 0 && pos < 32) {
         __ Dextm(i.OutputRegister(), i.InputRegister(0), i.InputInt8(1),
                  i.InputInt8(2));
       } else {