8307555: Reduce memory reads in x86 MD5 intrinsic

Backport-of: 43c8c65

src/hotspot/cpu/x86/macroAssembler_x86_md5.cpp

@@ -52,19 +52,16 @@
 // int com.sun.security.provider.MD5.implCompress0(byte[] b, int ofs)
 void MacroAssembler::fast_md5(Register buf, Address state, Address ofs, Address limit, bool multi_block) {
 
- Label start, done_hash, loop0;
+ Label done_hash, loop0;
 
- bind(start);
-
- bind(loop0);
-
- // Save hash values for addition after rounds
  movptr(rdi, state);
  movl(rax, Address(rdi, 0));
  movl(rbx, Address(rdi, 4));
  movl(rcx, Address(rdi, 8));
  movl(rdx, Address(rdi, 12));
 
+ bind(loop0);
+
 #define FF(r1, r2, r3, r4, k, s, t) \
  addl(r1, t); \
  movl(rsi, r3); \
@@ -189,10 +186,14 @@ void MacroAssembler::fast_md5(Register buf, Address state, Address ofs, Address
 
  // write hash values back in the correct order
  movptr(rdi, state);
- addl(Address(rdi, 0), rax);
- addl(Address(rdi, 4), rbx);
- addl(Address(rdi, 8), rcx);
- addl(Address(rdi, 12), rdx);
+ addl(rax, Address(rdi, 0));
+ movl(Address(rdi, 0), rax);
+ addl(rbx, Address(rdi, 4));
+ movl(Address(rdi, 4), rbx);
+ addl(rcx, Address(rdi, 8));
+ movl(Address(rdi, 8), rcx);
+ addl(rdx, Address(rdi, 12));
+ movl(Address(rdi, 12), rdx);
 
  if (multi_block) {
  // increment data pointer and loop if more to process