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Hi everyone, vmkit requires to know the size of a jitted method before emitting the method. This allows to allocate the correct size for the method. The attached patch creates this functionality when the flag SizedMemoryCode is on. In order to implement this functionality, i had to virtualize some MachineCodeEmitter functions. Is it OK to commit the patch? Thanks, Nicolas --------------

Hi Evan, Evan Cheng wrote: > 1) How are you computing size of the method being > jitted? I add a new pass with addSimpleCodeEmitter, with the emitter being a SizeEmitter. Since the target calls the emitter with functions such as writeByte, writeWord, etc.... the SizeEmitter class implements these function by incrementing a counter. At the end of the pass, the code size of the function is known. > 2) Why not simply add the functionality of allocating emissi...

...; + > /// PerformTailCallOpt - This flag is enabled when -tailcallopt is > specified > /// on the commandline. When the flag is on, the target will > perform tail call > /// optimization (pop the caller's stack) providing it supports it. > Index: include/llvm/CodeGen/SizeEmitter.h > =================================================================== > --- include/llvm/CodeGen/SizeEmitter.h (revision 0) > +++ include/llvm/CodeGen/SizeEmitter.h (revision 0) > @@ -0,0 +1,116 @@ > +//===-- llvm/CodeGen/MachineCodeEmitter.h - Code emission -------*- > C++...

On Apr 1, 2008, at 12:50 AM, Nicolas Geoffray wrote: > Hi Evan, > > Evan Cheng wrote: >> 1) How are you computing size of the method being >> jitted? > > I add a new pass with addSimpleCodeEmitter, with the emitter being a > SizeEmitter. Since the target calls the emitter with functions such as > writeByte, writeWord, etc.... the SizeEmitter class implements these > function by incrementing a counter. > > At the end of the pass, the code size of the function is known. That's a hack. :-) Some targets already have...

...for all targets, is not very intrusive and requires fewer code, hence introduces fewer bugs ;-) > > Suppose you have the size, can't you pass the desired buffer size to > MachineCodeEmitter and have it do the right thing? Sure, that's what I'm doing. The emitter with the SizeEmitter class will give the accurate size to the MachineCodeEmitter. And the MachineCodeEmitter will emit the instructions in the buffer. My solution is surely using things in a way that wasn't intended, but it works fine and for all targets. Is this really a stopper for integrating it? (You can...

...plicated code). Nicolas > Evan > > >> >>> Suppose you have the size, can't you pass the desired buffer size to >>> MachineCodeEmitter and have it do the right thing? >>> >> Sure, that's what I'm doing. The emitter with the SizeEmitter class >> will >> give the accurate size to the MachineCodeEmitter. And the >> MachineCodeEmitter will emit the instructions in the buffer. >> >> My solution is surely using things in a way that wasn't intended, >> but it >> works fine and for all...

...van >> >> >>> >>>> Suppose you have the size, can't you pass the desired buffer size >>>> to >>>> MachineCodeEmitter and have it do the right thing? >>>> >>> Sure, that's what I'm doing. The emitter with the SizeEmitter class >>> will >>> give the accurate size to the MachineCodeEmitter. And the >>> MachineCodeEmitter will emit the instructions in the buffer. >>> >>> My solution is surely using things in a way that wasn't intended, >>> but it >>>...

...e logic is all there in emitMemModRMByte. What do you think? Evan > > >> >> Suppose you have the size, can't you pass the desired buffer size to >> MachineCodeEmitter and have it do the right thing? > > Sure, that's what I'm doing. The emitter with the SizeEmitter class > will > give the accurate size to the MachineCodeEmitter. And the > MachineCodeEmitter will emit the instructions in the buffer. > > My solution is surely using things in a way that wasn't intended, > but it > works fine and for all targets. Is this really a st...

...gt; Suppose you have the size, can't you pass the desired buffer size >>>>> to >>>>> MachineCodeEmitter and have it do the right thing? >>>>> >>>>> >>>> Sure, that's what I'm doing. The emitter with the SizeEmitter class >>>> will >>>> give the accurate size to the MachineCodeEmitter. And the >>>> MachineCodeEmitter will emit the instructions in the buffer. >>>> >>>> My solution is surely using things in a way that wasn't intended, >>>...

...pose you have the size, can't you pass the desired buffer size >>>>>> to >>>>>> MachineCodeEmitter and have it do the right thing? >>>>>> >>>>>> >>>>> Sure, that's what I'm doing. The emitter with the SizeEmitter >>>>> class >>>>> will >>>>> give the accurate size to the MachineCodeEmitter. And the >>>>> MachineCodeEmitter will emit the instructions in the buffer. >>>>> >>>>> My solution is surely using things in a...