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gpu-compute: Changing reconvergenceStack type

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std::stack has no iterators, therefore the reconvergence stack can't be
iterated without poping elements off. We will be using std::list instead to be
able to iterate for saving and restoring purposes.
This commit is contained in:
Alexandru Dutu 2016-09-16 12:29:01 -04:00
parent d5c8c5d3db
commit 7918376450
2 changed files with 29 additions and 36 deletions
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14
src/gpu-compute/wavefront.cc
View file

@ -873,7 +873,7 @@ Wavefront::pushToReconvergenceStack(uint32_t pc, uint32_t rpc,
const VectorMask& mask)
{
assert(mask.count());
reconvergenceStack.emplace(new ReconvergenceStackEntry(pc, rpc, mask));
reconvergenceStack.emplace_back(new ReconvergenceStackEntry{pc, rpc, mask});
}
void
@ -886,7 +886,7 @@ Wavefront::popFromReconvergenceStack()
execMask().to_string<char, std::string::traits_type,
std::string::allocator_type>().c_str(), pc());
reconvergenceStack.pop();
reconvergenceStack.pop_back();
DPRINTF(WavefrontStack, "%3i %s\n", pc(),
execMask().to_string<char, std::string::traits_type,
@ -904,32 +904,32 @@ Wavefront::discardFetch()
uint32_t
Wavefront::pc() const
{
return reconvergenceStack.top()->pc;
return reconvergenceStack.back()->pc;
}
uint32_t
Wavefront::rpc() const
{
return reconvergenceStack.top()->rpc;
return reconvergenceStack.back()->rpc;
}
VectorMask
Wavefront::execMask() const
{
return reconvergenceStack.top()->execMask;
return reconvergenceStack.back()->execMask;
}
bool
Wavefront::execMask(int lane) const
{
return reconvergenceStack.top()->execMask[lane];
return reconvergenceStack.back()->execMask[lane];
}
void
Wavefront::pc(uint32_t new_pc)
{
reconvergenceStack.top()->pc = new_pc;
reconvergenceStack.back()->pc = new_pc;
}
uint32_t

51
src/gpu-compute/wavefront.hh
View file

@ -52,6 +52,27 @@
static const int MAX_NUM_INSTS_PER_WF = 12;
/**
* A reconvergence stack entry conveys the necessary state to implement
* control flow divergence.
*/
struct ReconvergenceStackEntry {
/**
* PC of current instruction.
*/
uint32_t pc;
/**
* PC of the immediate post-dominator instruction, i.e., the value of
* @a pc for the first instruction that will be executed by the wavefront
* when a reconvergence point is reached.
*/
uint32_t rpc;
/**
* Execution mask.
*/
VectorMask execMask;
};
/*
* Arguments for the hsail opcode call, are user defined and variable length.
* The hardware/finalizer can support arguments in hardware or use memory to
@ -120,34 +141,6 @@ class CallArgMem
}
};
/**
* A reconvergence stack entry conveys the necessary state to implement
* control flow divergence.
*/
class ReconvergenceStackEntry {
public:
ReconvergenceStackEntry(uint32_t new_pc, uint32_t new_rpc,
VectorMask new_mask) : pc(new_pc), rpc(new_rpc),
execMask(new_mask) {
}
/**
* PC of current instruction.
*/
uint32_t pc;
/**
* PC of the immediate post-dominator instruction, i.e., the value of
* @a pc for the first instruction that will be executed by the wavefront
* when a reconvergence point is reached.
*/
uint32_t rpc;
/**
* Execution mask.
*/
VectorMask execMask;
};
class Wavefront : public SimObject
{
public:
@ -368,7 +361,7 @@ class Wavefront : public SimObject
* point (branch instruction), and shrinks every time the wavefront
* reaches a reconvergence point (immediate post-dominator instruction).
*/
std::stack<std::unique_ptr<ReconvergenceStackEntry>> reconvergenceStack;
std::deque<std::unique_ptr<ReconvergenceStackEntry>> reconvergenceStack;
};
#endif // __WAVEFRONT_HH__