diff options
| author | Chris Lattner <sabre@nondot.org> | 2011-04-09 06:57:13 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2011-04-09 06:57:13 +0000 |
| commit | c3e4e59d1017178fdff33d6e34635f498c98592f (patch) | |
| tree | 0b8288ffb5253fd750ada8ef41f1bd1e0bc559e7 /lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | |
| parent | 9055ccdb6b33607e32ac83a8e9289fba44d1989a (diff) | |
Avoid excess precision issues that lead to generating host-compiler-specific code.
Switch lowering probably shouldn't be using FP for this. This resolves PR9581.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129199 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp index f751bb708e..8fb881b270 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -2019,9 +2019,13 @@ bool SelectionDAGBuilder::handleBTSplitSwitchCase(CaseRec& CR, APInt Range = ComputeRange(LEnd, RBegin); assert((Range - 2ULL).isNonNegative() && "Invalid case distance"); - double LDensity = (double)LSize.roundToDouble() / + // Use volatile double here to avoid excess precision issues on some hosts, + // e.g. that use 80-bit X87 registers. + volatile double LDensity = + (double)LSize.roundToDouble() / (LEnd - First + 1ULL).roundToDouble(); - double RDensity = (double)RSize.roundToDouble() / + volatile double RDensity = + (double)RSize.roundToDouble() / (Last - RBegin + 1ULL).roundToDouble(); double Metric = Range.logBase2()*(LDensity+RDensity); // Should always split in some non-trivial place |