6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-08-23 02:29:18 +00:00
Code Issues Projects Releases Wiki Activity

Clarify that duplicate edges are not allowed in the Machine CFG.

Browse Source 
LLVM IR has labeled duplicate CFG edges, but since Machine CFG edges
don't have labels, it doesn't make sense to allow duplicates. There is
no way of telling what the edges mean.

Duplicate CFG edges cause confusion when dealing with edge weights. It
seems that code producing duplicate CFG edges usually does the wrong
thing with edge weights.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162227 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen 2012-08-20 21:05:58 +00:00
parent 228e3f5fac
commit 2c5a960b0e
1 changed files with 2 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
include/llvm/CodeGen/MachineBasicBlock.h
View File

@ -351,6 +351,8 @@ public:
/// parameter is stored in Weights list and it may be used by
/// MachineBranchProbabilityInfo analysis to calculate branch probability.
///
/// Note that duplicate Machine CFG edges are not allowed.
///
void addSuccessor(MachineBasicBlock *succ, uint32_t weight = 0);
/// removeSuccessor - Remove successor from the successors list of this