[CodeGen] Fix formatting and comments (NFC)
llvm-svn: 363947
diff --git a/llvm/lib/CodeGen/SwitchLoweringUtils.cpp b/llvm/lib/CodeGen/SwitchLoweringUtils.cpp
index 1909ce1..53b6940 100644
--- a/llvm/lib/CodeGen/SwitchLoweringUtils.cpp
+++ b/llvm/lib/CodeGen/SwitchLoweringUtils.cpp
@@ -27,7 +27,6 @@
// FIXME: A range of consecutive cases has 100% density, but only requires one
// comparison to lower. We should discriminate against such consecutive ranges
// in jump tables.
-
return (HighCase - LowCase).getLimitedValue((UINT64_MAX - 1) / 100) + 1;
}
@@ -56,14 +55,15 @@
if (!TLI->areJTsAllowed(SI->getParent()->getParent()))
return;
- const int64_t N = Clusters.size();
const unsigned MinJumpTableEntries = TLI->getMinimumJumpTableEntries();
const unsigned SmallNumberOfEntries = MinJumpTableEntries / 2;
+ // Bail if not enough cases.
+ const int64_t N = Clusters.size();
if (N < 2 || N < MinJumpTableEntries)
return;
- // TotalCases[i]: Total nbr of cases in Clusters[0..i].
+ // Accumulated number of cases in each cluster and those prior to it.
SmallVector<unsigned, 8> TotalCases(N);
for (unsigned i = 0; i < N; ++i) {
const APInt &Hi = Clusters[i].High->getValue();
@@ -73,11 +73,12 @@
TotalCases[i] += TotalCases[i - 1];
}
- // Cheap case: the whole range may be suitable for jump table.
uint64_t Range = getJumpTableRange(Clusters,0, N - 1);
uint64_t NumCases = getJumpTableNumCases(TotalCases, 0, N - 1);
assert(NumCases < UINT64_MAX / 100);
assert(Range >= NumCases);
+
+ // Cheap case: the whole range may be suitable for jump table.
if (TLI->isSuitableForJumpTable(SI, NumCases, Range)) {
CaseCluster JTCluster;
if (buildJumpTable(Clusters, 0, N - 1, SI, DefaultMBB, JTCluster)) {
@@ -131,10 +132,11 @@
// Search for a solution that results in fewer partitions.
for (int64_t j = N - 1; j > i; j--) {
// Try building a partition from Clusters[i..j].
- uint64_t Range = getJumpTableRange(Clusters, i, j);
- uint64_t NumCases = getJumpTableNumCases(TotalCases, i, j);
+ Range = getJumpTableRange(Clusters, i, j);
+ NumCases = getJumpTableNumCases(TotalCases, i, j);
assert(NumCases < UINT64_MAX / 100);
assert(Range >= NumCases);
+
if (TLI->isSuitableForJumpTable(SI, NumCases, Range)) {
unsigned NumPartitions = 1 + (j == N - 1 ? 0 : MinPartitions[j + 1]);
unsigned Score = j == N - 1 ? 0 : PartitionsScore[j + 1];