PrintOptoAssembly output example

gistfile1.txt

// -XX::CompileOnly=sum::doit would narrow down the method to compile, but it
// is not used here.

$ ~/jdk1.7.0-b147/fastdebug/bin/java -XX:+PrintOptoAssembly sum
VM option '+PrintOptoAssembly'
{method} 
 - klass: {other class}
 - this oop:          0x911f8110
 - method holder:     'sum'
 - constants:         0x911f7e10 constant pool [32] for 'sum' cache=0x911f86b0
 - access:            0xc1000008  static 
 - name:              'doit'
 - signature:         '()I'
 - max stack:         2
 - max locals:        2
 - size of params:    0
 - method size:       24
 - vtable index:      -2
 - i2i entry:         0xb470be20
 - adapter:           0x091c0598
 - compiled entry     0xb47aada5
 - code size:         22
 - code start:        0x911f80f0
 - code end (excl):   0x911f8106
 - method data:       0x911f8c40
 - checked ex length: 0
 - linenumber start:  0x911f8106
 - localvar length:   0
#
#  int (  )
#
# -- Old esp -- Framesize: 16 --
#r045 esp+12: return address
#r044 esp+ 8: pad2, in_preserve
#r043 esp+ 4: pad2, in_preserve
#r042 esp+ 0: Fixed slot 0
#
abababab   N1: #	B1 <- B5  Freq: 1
abababab
000   B1: #	B2 <- BLOCK HEAD IS JUNK   Freq: 1
000   	PUSHL  EBP
	SUB    ESP,8	# Create frame
007   	XOR    EAX,EAX
009   	MOV    EBX,#1
      	NOP 	# 2 bytes pad for loops and calls

010   B2: #	B2 B3 <- B1 B2 	Loop: B2-B2 inner main of N14 Freq: 100.967
010   	ADD    EAX,EBX
012   	ADD    EAX,EBX
014   	ADD    EAX,EBX
016   	ADD    EAX,EBX
018   	ADD    EAX,EBX
01a   	ADD    EAX,EBX
01c   	ADD    EAX,EBX
01e   	ADD    EAX,EBX
020   	ADD    EBX,#8
023   	ADD    EAX,#28
026   	CMP    EBX,#97
029   	Jl,s  B2	# Loop end  P=0.990096 C=205333.000000
029
02b   B3: #	B5 B4 <- B2  Freq: 1
02b   	CMP    EBX,#100
02e   	Jge,s  B5  P=0.500000 C=-1.000000
02e
030   B4: #	B4 B5 <- B3 B4 	Loop: B4-B4 inner post of N90 Freq: 1
030   	ADD    EAX,EBX
032   	INC    EBX
033   	CMP    EBX,#100
036   	Jl,s  B4	# Loop end  P=0.500000 C=205333.000000
036
038   B5: #	N1 <- B4 B3  Freq: 1
038   	ADD    ESP,8	# Destroy frame
	POPL   EBP
	TEST   PollPage,EAX	! Poll Safepoint
	
042   	RET
042

{method} 
 - klass: {other class}
 - this oop:          0x911f8048
 - method holder:     'sum'
 - constants:         0x911f7e10 constant pool [32] for 'sum' cache=0x911f86b0
 - access:            0xc1000009  public static 
 - name:              'main'
 - signature:         '([Ljava/lang/String;)V'
 - max stack:         4
 - max locals:        4
 - size of params:    1
 - method size:       24
 - vtable index:      -2
 - i2i entry:         0xb470be20
 - adapter:           0x091c056c
 - compiled entry     0xb47aaee8
 - code size:         34
 - code start:        0x911f8018
 - code end (excl):   0x911f803a
 - method data:       0x911f8cd0
 - checked ex length: 0
 - linenumber start:  0x911f803a
 - localvar length:   0
#
#  void ( rawptr:BotPTR )
#
#r000 ecx   : parm 0: rawptr:BotPTR
# -- Old esp -- Framesize: 32 --
#r045 esp+28: return address
#r044 esp+24: pad2, in_preserve
#r043 esp+20: pad2, in_preserve
#r042 esp+16: Fixed slot 0
#r049 esp+12: spill
#r048 esp+ 8: spill
#r047 esp+ 4: spill
#r046 esp+ 0: outgoing argument
#
000   N28: #	B1 <- BLOCK HEAD IS JUNK   Freq: 1
000   	INT3
      	NOP 	# 3 bytes pad for loops and calls

008   B1: #	N28 <- BLOCK HEAD IS JUNK   Freq: 1
008   	# stack bang
	PUSHL  EBP
	SUB    ESP,24	# Create frame
016   	MOV    [ESP + #0],ECX
019   	CALL_LEAF,runtime  OSR_migration_end
        No JVM State Info
        # 
01e   	MOV    ECX,#24
023   	CALL,static  wrapper for: uncommon_trap(reason='unloaded' action='reinterpret' index='24')
        # sum::main @ bci:26  L[0]=_ L[1]=_ L[2]=_ L[3]=_ STK[0]=#10000 STK[1]=_
        # OopMap{off=40}
028   	INT3   ; ShouldNotReachHere
028

sum.java

public class sum {
  public static void main(String[] args) {
    long r = 0L;
    for (int i = 0; i < 100000; i++) {
      r += doit();
    }
    try { Thread.sleep(10*1000); } catch (InterruptedException ie) {}
  }
  static int doit() {
    int sm = 0;
    for (int i = 0; i < 100; i++) sm += i;
    return sm;
  }
}