S390: [wasm] Int64Lowering of Int64Sub.

src/s390/macro-assembler-s390.cc

Index: src/s390/macro-assembler-s390.cc
diff --git a/src/s390/macro-assembler-s390.cc b/src/s390/macro-assembler-s390.cc
index 37db6df1ba46859c5abc311562450d460f38f60e..789fa5d575d09efb569e6af647c1b94446e6f37c 100644
--- a/src/s390/macro-assembler-s390.cc
+++ b/src/s390/macro-assembler-s390.cc
@@ -4076,6 +4076,42 @@ void MacroAssembler::AddLogicalP(Register dst, const MemOperand& opnd) {
 //  Subtract Instructions
 //----------------------------------------------------------------------------
 
+// Subtract Logical With Carry 32-bit (Register dst = Register src1 - Register
+// src2)
+void MacroAssembler::SubLogicalWithBorrow32(Register dst, Register src1,
+                                            Register src2) {
+  if (!dst.is(src2) && !dst.is(src1)) {
+    lr(dst, src1);
+    slbr(dst, src2);
+  } else if (!dst.is(src2)) {
+    // dst == src1
+    DCHECK(dst.is(src1));
+    slbr(dst, src2);
+  } else {
+    // dst == src2
+    DCHECK(dst.is(src2));
+    lr(r0, dst);
+    SubLogicalWithBorrow32(dst, src1, r0);
+  }
+}
+
+// Subtract Logical 32-bit (Register dst = Register src1 - Register src2)
+void MacroAssembler::SubLogical32(Register dst, Register src1, Register src2) {
+  if (!dst.is(src2) && !dst.is(src1)) {
+    lr(dst, src1);
+    slr(dst, src2);
+  } else if (!dst.is(src2)) {
+    // dst == src1
+    DCHECK(dst.is(src1));
+    slr(dst, src2);
+  } else {
+    // dst == src2
+    DCHECK(dst.is(src2));
+    lr(r0, dst);
+    SubLogical32(dst, src1, r0);
+  }
+}
+
 // Subtract 32-bit (Register dst = Register dst - Immediate opnd)
 void MacroAssembler::Sub32(Register dst, const Operand& imm) {
   Add32(dst, Operand(-(imm.imm_)));