8305783: x86_64: Optimize AbsI and AbsL

Reviewed-by: jkarthikeyan, thartmann

Author: Quan Anh Mai

src/hotspot/cpu/x86/x86_64.ad

@@ -8462,44 +8462,34 @@ instruct xchgN( memory mem, rRegN newval) %{
 //----------Abs Instructions-------------------------------------------
 
 // Integer Absolute Instructions
-instruct absI_rReg(rRegI dst, rRegI src, rRegI tmp, rFlagsReg cr)
+instruct absI_rReg(rRegI dst, rRegI src, rFlagsReg cr)
 %{
   match(Set dst (AbsI src));
-  effect(TEMP dst, TEMP tmp, KILL cr);
-  format %{ "movl $tmp, $src\n\t"
-            "sarl $tmp, 31\n\t"
-            "movl $dst, $src\n\t"
-            "xorl $dst, $tmp\n\t"
-            "subl $dst, $tmp\n"
-          %}
+  effect(TEMP dst, KILL cr);
+  format %{ "xorl    $dst, $dst\t# abs int\n\t"
+            "subl    $dst, $src\n\t"
+            "cmovll  $dst, $src" %}
   ins_encode %{
-    __ movl($tmp$$Register, $src$$Register);
-    __ sarl($tmp$$Register, 31);
-    __ movl($dst$$Register, $src$$Register);
-    __ xorl($dst$$Register, $tmp$$Register);
-    __ subl($dst$$Register, $tmp$$Register);
+    __ xorl($dst$$Register, $dst$$Register);
+    __ subl($dst$$Register, $src$$Register);
+    __ cmovl(Assembler::less, $dst$$Register, $src$$Register);
   %}
 
   ins_pipe(ialu_reg_reg);
 %}
 
 // Long Absolute Instructions
-instruct absL_rReg(rRegL dst, rRegL src, rRegL tmp, rFlagsReg cr)
+instruct absL_rReg(rRegL dst, rRegL src, rFlagsReg cr)
 %{
   match(Set dst (AbsL src));
-  effect(TEMP dst, TEMP tmp, KILL cr);
-  format %{ "movq $tmp, $src\n\t"
-            "sarq $tmp, 63\n\t"
-            "movq $dst, $src\n\t"
-            "xorq $dst, $tmp\n\t"
-            "subq $dst, $tmp\n"
-          %}
+  effect(TEMP dst, KILL cr);
+  format %{ "xorl    $dst, $dst\t# abs long\n\t"
+            "subq    $dst, $src\n\t"
+            "cmovlq  $dst, $src" %}
   ins_encode %{
-    __ movq($tmp$$Register, $src$$Register);
-    __ sarq($tmp$$Register, 63);
-    __ movq($dst$$Register, $src$$Register);
-    __ xorq($dst$$Register, $tmp$$Register);
-    __ subq($dst$$Register, $tmp$$Register);
+    __ xorl($dst$$Register, $dst$$Register);
+    __ subq($dst$$Register, $src$$Register);
+    __ cmovq(Assembler::less, $dst$$Register, $src$$Register);
   %}
 
   ins_pipe(ialu_reg_reg);