diff options
| author | Evan Cheng <evan.cheng@apple.com> | 2008-03-12 07:52:15 +0000 |
|---|---|---|
| committer | Evan Cheng <evan.cheng@apple.com> | 2008-03-12 07:52:15 +0000 |
| commit | 136a24742c63863077fc5d914cf3e9755b15d85b (patch) | |
| tree | 6584014e309dd5c05073ea73b3811ca8cb7f72f3 | |
| parent | 6ff0b822b4cea09b3d2f64c2937db6425a013868 (diff) | |
| download | bcm5719-llvm-136a24742c63863077fc5d914cf3e9755b15d85b.tar.gz bcm5719-llvm-136a24742c63863077fc5d914cf3e9755b15d85b.zip | |
Document an implementation detail about EXTRACT_SUBREG and INSERT_SUBREG sub-register operand.
llvm-svn: 48283
| -rw-r--r-- | llvm/include/llvm/CodeGen/SelectionDAGNodes.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/llvm/include/llvm/CodeGen/SelectionDAGNodes.h b/llvm/include/llvm/CodeGen/SelectionDAGNodes.h index b2c354dae1d..49012b4b0e7 100644 --- a/llvm/include/llvm/CodeGen/SelectionDAGNodes.h +++ b/llvm/include/llvm/CodeGen/SelectionDAGNodes.h @@ -320,6 +320,9 @@ namespace ISD { // EXTRACT_SUBREG - This node is used to extract a sub-register value. // This node takes a superreg and a constant sub-register index as operands. + // Note sub-register indices must be increasing. That is, if the + // sub-register index of a 8-bit sub-register is N, then the index for a + // 16-bit sub-register must be at least N+1. EXTRACT_SUBREG, // INSERT_SUBREG - This node is used to insert a sub-register value. |
