8204267 - Generate comments in -XX:+PrintInterpreter to link to source code

[Ioi Lam]

Hi Folks,

I've found it very hard to understand the assembler code printed by 
-XX:+PrintInterpreter. Since the C++ source code that generates the 
interpreter is fairly well documented, it might be a good idea to print 
out the source code along with the assembler code.

I've done a quick proof-of-concept by hacking the "__" macro that's used 
throughout the CPU-dependent sources.

Please let me know if you think this is worth doing. If so, I will try 
to finish it up and post a real RFR.

Thanks
- Ioi


https://bugs.openjdk.java.net/browse/JDK-8204267
http://cr.openjdk.java.net/~iklam/misc/8204267-print-interpreter-comments.v00
http://cr.openjdk.java.net/~iklam/misc/8204267-print-interpreter-comments.v00/hs_interp.S

Here are some examples (if the mailer screws up the long lines, please 
click the above link):

ifeq  153 ifeq  [0x00007f830cc93da0, 0x00007f830cc941c0] 1056 bytes

mov    (%rsp),%eax
add    $0x8,%rsp
test   %eax,%eax           ;; 2353:   __ testl(rax, rax);
jne    0x00007f830cc94177  ;; 2354:   __ jcc(j_not(cc), not_taken);
mov    -0x18(%rbp),%rcx    ;; 2120:   __ get_method(rcx); // rcx holds 
method
mov    -0x28(%rbp),%rax    ;; 2121:   __ profile_taken_branch(rax, rbx); 
// rax holds updated MDP, rbx
test   %rax,%rax
je     0x00007f830cc93dd8
mov    0x8(%rax),%rbx
add    $0x1,%rbx
sbb    $0x0,%rbx
mov    %rbx,0x8(%rax)
add    0x10(%rax),%rax
mov    %rax,-0x28(%rbp)
movswl 0x1(%r13),%edx      ;; 2133:     __ load_signed_short(rdx, 
at_bcp(1));
bswap  %edx                ;; 2135:   __ bswapl(rdx);
sar    $0x10,%edx          ;; 2138:     __ sarl(rdx, 16);
movslq %edx,%rdx           ;; 2140:   LP64_ONLY(__ movl2ptr(rdx, rdx));
add    %rdx,%r13           ;; 2164:   __ addptr(rbcp, rdx);
test   %edx,%edx           ;; 2179:     __ testl(rdx, rdx);             
// check if forward or backward branch
jns    0x00007f830cc93eec  ;; 2180:     __ jcc(Assembler::positive, 
dispatch); // count only if backward branch
mov    0x18(%rcx),%rax     ;; 2184:     __ movptr(rax, Address(rcx, 
Method::method_counters_offset()));
test   %rax,%rax           ;; 2185:     __ testptr(rax, rax);
jne    0x00007f830cc93ead  ;; 2186:     __ jcc(Assembler::notZero, 
has_counters);
push   %rdx                ;; 2187:     __ push(rdx);
push   %rcx                ;; 2188:     __ push(rcx);
callq  0x00007f830cc93e09  ;; 2189:     __ call_VM(noreg, 
CAST_FROM_FN_PTR(address, InterpreterRuntime::build_method_counters),