Displaying 4 results from an estimated 4 matches for "optimizethumb2jumpt".
2013 Jul 29
0
[LLVMdev] Question on optimizeThumb2JumpTables
Hi Jakob,
You're the unfortunate soul who last touched the constant island pass,
right? Do you happen to have any insight for Daniel?
Chad
On Tue, Jul 23, 2013 at 9:55 AM, Daniel Stewart <stewartd at codeaurora.org>wrote:
> In looking at the code in
> ARMConstantislandPass.cpp::optimizeThumb2JumpTables(), I see that there is
> the following condition for not creating tbb-based jump tables:****
>
> ** **
>
> // The instruction should be a tLEApcrel or t2LEApcrelJT; we want***
> *
>
> // to delete it as well.****
>
> *MachineInstr* *LeaMI = PrevI...
2013 Jul 29
1
[LLVMdev] Question on optimizeThumb2JumpTables
...niel?
Sorry, no. I don't remember working with that particular bit of code. You could try digging through the commit logs.
Thanks,
/jakob
> On Tue, Jul 23, 2013 at 9:55 AM, Daniel Stewart <stewartd at codeaurora.org> wrote:
> In looking at the code in ARMConstantislandPass.cpp::optimizeThumb2JumpTables(), I see that there is the following condition for not creating tbb-based jump tables:
>
>
>
> // The instruction should be a tLEApcrel or t2LEApcrelJT; we want
>
> // to delete it as well.
>
> MachineInstr *LeaMI = PrevI;
>
> if ((L...
2013 Jul 23
2
[LLVMdev] Question on optimizeThumb2JumpTables
In looking at the code in
ARMConstantislandPass.cpp::optimizeThumb2JumpTables(), I see that there is
the following condition for not creating tbb-based jump tables:
// The instruction should be a tLEApcrel or t2LEApcrelJT; we want
// to delete it as well.
MachineInstr *LeaMI = PrevI;
if ((LeaMI->getOpcode() != ARM::tLEApcrelJT &&...
2018 Aug 11
2
MachineInstr sizes for ARM jumptables
...unsigned Size = JT[JTI].MBBs.size() * sizeof(uint32_t);
----------------------------------------------------------------------
Obviously, a size of 4 bytes per entry is incorrect for jump tables
consisting of byte or halfword entries.
Additionally, when trying to optimize for table size later in
optimizeThumb2JumpTables, the opcode is updated without updating the
size (lib/Target/ARM/ARMConstantIslandPass.cpp:2229):
----------------------------------------------------------------------
unsigned JTOpc = ByteOk ? ARM::JUMPTABLE_TBB : ARM::JUMPTABLE_TBH;
---------------------------------------------------------...