Displaying 5 results from an estimated 5 matches for "isjumptable".
2007 Aug 19
1
[LLVMdev] MBB Critical edges
...add one method to
>> TargetInstrInfo to tell me when an instruction is an indirect jump -
>> TargetInstrInfo::tii.isIndirectJump(opcode). When that is the case, I
>> update the jump table using:
>>
>> // Change jumps to go to the new basic block:
>> if(isJumpTable) {
>> mf.getJumpTableInfo()->ReplaceMBBInJumpTables(& dst,
>> crit_mbb);
>> }
>>
>> where dst was the old basic block, and crit_mbb is the new one,
>> created to
>> remove a critical edge. I think this should solve the problem. If you
&...
2007 Aug 17
2
[LLVMdev] MBB Critical edges
...on.
At least I think I've solved it. I had to add one method to
TargetInstrInfo to tell me when an instruction is an indirect jump -
TargetInstrInfo::tii.isIndirectJump(opcode). When that is the case, I
update the jump table using:
// Change jumps to go to the new basic block:
if(isJumpTable) {
mf.getJumpTableInfo()->ReplaceMBBInJumpTables(& dst, crit_mbb);
}
where dst was the old basic block, and crit_mbb is the new one, created to
remove a critical edge. I think this should solve the problem. If you
want, I can give you the pass to break critical edges of mach...
2007 Aug 18
0
[LLVMdev] MBB Critical edges
...9;ve solved it. I had to add one method to
> TargetInstrInfo to tell me when an instruction is an indirect jump -
> TargetInstrInfo::tii.isIndirectJump(opcode). When that is the case, I
> update the jump table using:
>
> // Change jumps to go to the new basic block:
> if(isJumpTable) {
> mf.getJumpTableInfo()->ReplaceMBBInJumpTables(& dst,
> crit_mbb);
> }
>
> where dst was the old basic block, and crit_mbb is the new one,
> created to
> remove a critical edge. I think this should solve the problem. If you
> want, I can give you...
2007 Aug 17
0
[LLVMdev] MBB Critical edges
Sorry about the tardiness of my reply. My mail client has playing
tricks with me. :-)
I am assuming the issue has nothing to do the branch to jumptable
instructions but rather the MachineJumpTableInfo associated with every
MachineFunction? If so, please take a look at BranchFoldiing.cpp for
an example.
Evan
On Aug 10, 2007, at 12:30 PM, Fernando Magno Quintao Pereira wrote:
>
>
2007 Aug 10
2
[LLVMdev] MBB Critical edges
Hi all,
I have a pass to break critical edges of Machine Basic Blocks, but I
just discovered a bug (when compiling code for x86). The problem is 'jumpl
*%reg'. I don't know how to update the jump table for this type of
instruction. The code that I had (see below) does not update the jump
table, and the actual branch keeps jumping to the old basic block, instead
of the new.