6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-09-24 23:28:41 +00:00
Code Issues Projects Releases Wiki Activity

Fix constant folding through bitcasts by no longer relying on undefined behaviour (converting NaN values between float and double).

Browse Source 
SelectionDAG::getConstantFP(double Val, EVT VT, bool isTarget);
should not be used when Val is not a simple constant (as the comment in
SelectionDAG.h indicates). This patch avoids using this function
when folding an unknown constant through a bitcast, where it cannot be
guaranteed that Val will be a simple constant.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163703 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Kristof Beyls
2012-09-12 11:25:02 +00:00
parent d76f6eadc8
commit 789efbad2a
2 changed files with 12 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
lib/CodeGen/SelectionDAG/SelectionDAG.cpp
View File

@@ -2454,9 +2454,9 @@ SDValue SelectionDAG::getNode(unsigned Opcode, DebugLoc DL,
}
case ISD::BITCAST:
if (VT == MVT::f32 && C->getValueType(0) == MVT::i32)
return getConstantFP(Val.bitsToFloat(), VT);
return getConstantFP(APFloat(Val), VT);
else if (VT == MVT::f64 && C->getValueType(0) == MVT::i64)
return getConstantFP(Val.bitsToDouble(), VT);
return getConstantFP(APFloat(Val), VT);
break;
case ISD::BSWAP:
return getConstant(Val.byteSwap(), VT);