S390: Initial impl of turbofan compiler

src/compiler/wasm-linkage.cc

Index: src/compiler/wasm-linkage.cc
diff --git a/src/compiler/wasm-linkage.cc b/src/compiler/wasm-linkage.cc
index 3176fd3e2acabfc83be8fd628e4d5725d5328247..41acf55c441fc3413480286ab21f9eb5911fbab6 100644
--- a/src/compiler/wasm-linkage.cc
+++ b/src/compiler/wasm-linkage.cc
@@ -125,6 +125,24 @@ LinkageLocation stackloc(int i) {
 #define FP_PARAM_REGISTERS d1, d2, d3, d4, d5, d6, d7, d8
 #define FP_RETURN_REGISTERS d1, d2
 
+#elif V8_TARGET_ARCH_S390X
+// ===========================================================================
+// == s390x ==================================================================
+// ===========================================================================
+#define GP_PARAM_REGISTERS r2, r3, r4, r5, r6
+#define GP_RETURN_REGISTERS r2
+#define FP_PARAM_REGISTERS d0, d2, d4, d6
+#define FP_RETURN_REGISTERS d0, d2, d4, d6
+
+#elif V8_TARGET_ARCH_S390
+// ===========================================================================
+// == s390 ===================================================================
+// ===========================================================================
+#define GP_PARAM_REGISTERS r2, r3, r4, r5, r6
+#define GP_RETURN_REGISTERS r2, r3
+#define FP_PARAM_REGISTERS d0, d2
+#define FP_RETURN_REGISTERS d0, d2
+
 #else
 // ===========================================================================
 // == unknown ================================================================