6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-14 11:32:34 +00:00
Code Issues Projects Releases Wiki Activity

* Expose new pass DeadInstElimination

Browse Source 
* Add comments that describe the differences between the DCE passes


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@1553 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2002-01-23 05:47:35 +00:00
parent 80fceef49b
commit 17643a8c9d
1 changed files with 25 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
include/llvm/Transforms/Scalar/DCE.h
View File

@ -11,6 +11,26 @@
#include "llvm/Pass.h" #include "llvm/Pass.h"
#include "llvm/BasicBlock.h" #include "llvm/BasicBlock.h"
//===----------------------------------------------------------------------===//
// DeadInstElimination - This pass quickly removes trivially dead instructions
// without modifying the CFG of the function. It is a BasicBlockPass, so it
// runs efficiently when queued next to other BasicBlockPass's.
//
struct DeadInstElimination : public BasicBlockPass {
virtual bool runOnBasicBlock(BasicBlock *BB);
};
//===----------------------------------------------------------------------===//
// DeadCodeElimination - This pass is more powerful than DeadInstElimination,
// because it will remove dead basic blocks as well as all of the instructions
// contained within them. This pass is useful to run after another pass has
// reorganized the CFG and possibly modified control flow.
//
// TODO: In addition to DCE stuff, this also merges basic blocks together and
// otherwise simplifies control flow. This should be factored out of this pass
// eventually into it's own pass.
//
struct DeadCodeElimination : public MethodPass { struct DeadCodeElimination : public MethodPass {
// External Interface: // External Interface:
// //
@ -42,6 +62,11 @@ struct DeadCodeElimination : public MethodPass {
//===----------------------------------------------------------------------===//
// AgressiveDCE - This pass uses the SSA based Agressive DCE algorithm. This
// algorithm assumes instructions are dead until proven otherwise, which makes
// it more successful are removing non-obviously dead instructions.
//
struct AgressiveDCE : public MethodPass { struct AgressiveDCE : public MethodPass {
// DoADCE - Execute the Agressive Dead Code Elimination Algorithm // DoADCE - Execute the Agressive Dead Code Elimination Algorithm
// //