[HARMONY-6023] [drlvm][jit] Illegal CDQ deletion in int64 lowerer

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: DRLVM
• Environment: IA32 Windows
• Assignee: Unassigned
• Reporter: Xiaoming Gu
• Created: 19/Nov/08 15:34
• Updated: 08/Jul/09 01:50

Description

This bug happens in java.math.Division.divide() if early_prop bypassed. Following are the details:

before i8l pass
I170: (AD:t229:int64) =I8PseudoInst/MOVSX (AU:t228:I_32)
I171: (AD:v5:int64) =I8PseudoInst/MOV (AU:t229:int64)

after i8l pass
I783: o1017:U_32 =MOV t228:I_32
I785: (AD:o960:U_32) =CopyPseudoInst/MOV (AU:o1017:U_32)
I786: (AD:o961:I_32) =CopyPseudoInst/MOV (AU:o1018:I_32)

o1018 is not defined, which will cause an assertion error in webmaker pass.

(It looks there is nothing between early_prop and this bug. But with early_prop, I786 is deleted by the second cg_dce before webmaker. I don't know why I786 is not deleted if early_prop bypassed. With some investigation, I think there might be something wrong with liveness calculation during cg_dce. I'll do more when this bug is fixed.)

Issue Links

• is part of: HARMONY-6027 [drlvm][jit] An incorrect register assignment in graph coloring register allocation