This reverts merge request !9

(CPU/GPU/SPIR) based on policy.
Support for scheduling per iteration included.
Further testing required.

The SymVT stuff has not been moved yet, I removed it for now.
The test/VISC tests also have not been moved yet, so they may not
work.

(1) Changes to DFGraph.h for identifying streaming graphs and edges
(2) Added/modified launch, wait, push, pop intrinsics for streaming graphs
(3) Changes to DFG2LLVM_X86.cpp and DFG2LLVM.h pass to support code gen for streaming
(4) BuildDFG.cpp modified to create streaming edges
(5) Modified visc-rt.cpp and visc-rt.h to add runtime support for streaming

Revert back to using __visc__init and cleanup without arguments. That is, they are no more DFG specific, rather just hints for compiler to insert compilation code

(1) Working on implementation of further lowereing the visc api by breaking the
DFG launch call into init, launch, wait, cleanup. There are issues pending when
these require some kind of inter procedural analysis to link init, launch, wait
and cleanup. This is necessary during code generation.
(2) Also contains changes which simplify GenVISC pass by using macro for
identifying various source __visc__ calls

the graphID as reference. It is returned by the launch functions. Makes it
easier to write code
(2) BuildDFG support for data transfer to PTX nodes
(3) ClearDFG bugs fixed
(4) visc-rt modified
(5) Test case 3level.ll modified to match the new launch and wait intrinsic
format

M    llvm/test/VISC/unitTests/3level.ll
M    llvm/include/llvm/IR/DFGraph.h
M    llvm/include/llvm/IR/IntrinsicsVISC.td
M    llvm/projects/visc-rt/visc-rt.cpp
M    llvm/lib/Transforms/BuildDFG/BuildDFG.cpp
M    llvm/lib/Transforms/DFG2LLVM_X86/DFG2LLVM_X86.cpp
M    llvm/lib/Transforms/ClearDFG/ClearDFG.cpp

(2) Modified BuildDFG and DFG2LLVM_X86 to generate the correct calls to visc
runtime
(3) Modified the test cases to the new launch wait semantics of visc
(4) Added Wait intrinsic to VISC and modified the argument list of launch and
wait

(2) Have to generate code for a new Launch function which can be called by
pthread_create and which extracts the root inputs from a memory location i8*.
(3) Formatted the different files to be more consisitent with LLVM coding
principles
M    llvm/include/llvm/BuildDFG/BuildDFG.h
M    llvm/include/llvm/IR/DFGraph.h
M    llvm/lib/Transforms/BuildDFG/BuildDFG.cpp
M    llvm/lib/Transforms/DFG2LLVM_X86/DFG2LLVM_X86.cpp

(2) Added codegen support for i/o bindings in dfg2llvm-x86 pass
M    llvm/include/llvm/BuildDFG/BuildDFG.h
M    llvm/include/llvm/IR/DFGraph.h
M    llvm/lib/Transforms/BuildDFG/BuildDFG.cpp
M    llvm/lib/Transforms/DFG2LLVM_X86/DFG2LLVM_X86.cpp

Next step is to add support for new bind intrinsic.
(2) Minor bug fixes
M    llvm/include/llvm/IR/DFGraph.h
M    llvm/lib/Transforms/BuildDFG/BuildDFG.cpp
M    llvm/lib/Transforms/DFG2LLVM_X86/DFG2LLVM_X86.cpp

(2) Updated the DFG2LLVM_X86 pass to pass correct dim limit values while
generating code for internal node

instructions being generated successfully.
(2) Updated DFNode class and BuildDFG pass to make all nodes have struct as
return type.
M    llvm/include/llvm/BuildDFG/BuildDFG.h
M    llvm/include/llvm/IR/DFGraph.h
M    llvm/include/llvm/IR/IntrinsicsVISC.td
M    llvm/lib/Transforms/BuildDFG/BuildDFG.cpp
M    llvm/lib/Transforms/DFG2LLVM_X86/DFG2LLVM_X86.cpp

intrinsic.

graph.
(2) Added support for various query intrinsics in leaf node code generation for
x86 including adding index and limit variables to leaf node function arguments.

2. Bug fix in a testcase.

refactored BuildDFG code. Now just addEdgeToDFGraph should be enough to make all the successor and predecessor changes to nodes

Removed warnings because of unused members of DFEdge class. Changed Source and Destination positions of DFEdge to unsigned

Changes to BuildDFG pass. Handle launch intrinsic. Added support for cast, isa, dyn_cast on DFNode. New test cases added.

intrinsic instructions with appropriate instructions/values).