[x64] Fix instruction selection for mov reg, Smi and TestMoveSmi

This CL fixed cmpq in TestMoveSmi by using cmp_tagged and further
optimizes Move(Register, Smi) for 31-bit negative Smi.

To move a Smi of -1 to register, the disassembly before the commit is as:
48c7c0feffffff    REX.W movq rax, 0xfffffffe

The disassembly after the commit is as:
b8feffffff        movl rax, 0xfffffffe

Bug: v8:12696
Change-Id: I6fafeec7959491ba8b084acf797c58910c2928fa
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3514654Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Haoyu Zhang <haoyu.zhang@intel.com>
Cr-Commit-Position: refs/heads/main@{#79475}

src/codegen/x64/macro-assembler-x64.cc

@@ -1463,8 +1463,8 @@ void TurboAssembler::Move(Register dst, Smi source) {
   } else if (SmiValuesAre32Bits()) {
     Move(dst, source.ptr(), RelocInfo::NO_INFO);
   } else {
-    intptr_t svalue = static_cast<intptr_t>(source.ptr());
-    Move(dst, svalue);
+    uint32_t uvalue = static_cast<uint32_t>(source.ptr());
+    Move(dst, uvalue);
   }
 }
 

test/cctest/test-macro-assembler-x64.cc

@@ -102,7 +102,7 @@ static void TestMoveSmi(MacroAssembler* masm, Label* exit, int id, Smi value) {
   __ movl(rax, Immediate(id));
   __ Move(rcx, value);
   __ Move(rdx, static_cast<intptr_t>(value.ptr()));
-  __ cmpq(rcx, rdx);
+  __ cmp_tagged(rcx, rdx);
   __ j(not_equal, exit);
 }