Handle UINT64_MAX edge case in switch lowering.
BUG=
R=jvoung@chromium.org, jvoung
Review URL: https://codereview.chromium.org/1247833003.
diff --git a/src/IceSwitchLowering.cpp b/src/IceSwitchLowering.cpp
index 06894e6..37e67c1 100644
--- a/src/IceSwitchLowering.cpp
+++ b/src/IceSwitchLowering.cpp
@@ -75,9 +75,13 @@
// Replace everything with a jump table
InstJumpTable *JumpTable =
InstJumpTable::create(Func, TotalRange, Inst->getLabelDefault());
- for (const CaseCluster &Case : CaseClusters)
- for (uint64_t I = Case.Low; I <= Case.High; ++I)
+ for (const CaseCluster &Case : CaseClusters) {
+ // Case.High could be UINT64_MAX which makes the loop awkward. Unwrap the
+ // last iteration to avoid wrap around problems.
+ for (uint64_t I = Case.Low; I < Case.High; ++I)
JumpTable->addTarget(I - MinValue, Case.Label);
+ JumpTable->addTarget(Case.High - MinValue, Case.Label);
+ }
CaseClusters.clear();
CaseClusters.emplace_back(MinValue, MaxValue, JumpTable);