+
+ // Compute the call-site table. The entry for an invoke has a try-range
+ // containing the call, a non-zero landing pad and an appropriate action.
+ // The entry for an ordinary call has a try-range containing the call and
+ // zero for the landing pad and the action. Calls marked 'nounwind' have
+ // no entry and must not be contained in the try-range of any entry - they
+ // form gaps in the table. Entries must be ordered by try-range address.
+ SmallVector<CallSiteEntry, 64> CallSites;
+
+ RangeMapType PadMap;
+ // Invokes and nounwind calls have entries in PadMap (due to being bracketed
+ // by try-range labels when lowered). Ordinary calls do not, so appropriate
+ // try-ranges for them need be deduced.
+ for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) {
+ const LandingPadInfo *LandingPad = LandingPads[i];
+ for (unsigned j = 0, E = LandingPad->BeginLabels.size(); j != E; ++j) {
+ unsigned BeginLabel = LandingPad->BeginLabels[j];
+ assert(!PadMap.count(BeginLabel) && "Duplicate landing pad labels!");
+ PadRange P = { i, j };
+ PadMap[BeginLabel] = P;
+ }
+ }
+
+ // The end label of the previous invoke or nounwind try-range.
+ unsigned LastLabel = 0;
+
+ // Whether there is a potentially throwing instruction (currently this means
+ // an ordinary call) between the end of the previous try-range and now.
+ bool SawPotentiallyThrowing = false;
+
+ // Whether the last callsite entry was for an invoke.
+ bool PreviousIsInvoke = false;
+
+ // Visit all instructions in order of address.
+ for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
+ I != E; ++I) {
+ for (MachineBasicBlock::const_iterator MI = I->begin(), E = I->end();
+ MI != E; ++MI) {
+ if (MI->getOpcode() != TargetInstrInfo::LABEL) {
+ SawPotentiallyThrowing |= MI->getDesc().isCall();
+ continue;
+ }
+
+ unsigned BeginLabel = MI->getOperand(0).getImm();
+ assert(BeginLabel && "Invalid label!");
+
+ // End of the previous try-range?
+ if (BeginLabel == LastLabel)
+ SawPotentiallyThrowing = false;
+
+ // Beginning of a new try-range?
+ RangeMapType::iterator L = PadMap.find(BeginLabel);
+ if (L == PadMap.end())
+ // Nope, it was just some random label.
+ continue;
+
+ PadRange P = L->second;
+ const LandingPadInfo *LandingPad = LandingPads[P.PadIndex];
+
+ assert(BeginLabel == LandingPad->BeginLabels[P.RangeIndex] &&
+ "Inconsistent landing pad map!");
+
+ // If some instruction between the previous try-range and this one may
+ // throw, create a call-site entry with no landing pad for the region
+ // between the try-ranges.
+ if (SawPotentiallyThrowing) {
+ CallSiteEntry Site = {LastLabel, BeginLabel, 0, 0};
+ CallSites.push_back(Site);
+ PreviousIsInvoke = false;
+ }
+
+ LastLabel = LandingPad->EndLabels[P.RangeIndex];
+ assert(BeginLabel && LastLabel && "Invalid landing pad!");
+
+ if (LandingPad->LandingPadLabel) {
+ // This try-range is for an invoke.
+ CallSiteEntry Site = {BeginLabel, LastLabel,
+ LandingPad->LandingPadLabel, FirstActions[P.PadIndex]};
+
+ // Try to merge with the previous call-site.
+ if (PreviousIsInvoke) {
+ CallSiteEntry &Prev = CallSites[CallSites.size()-1];
+ if (Site.PadLabel == Prev.PadLabel && Site.Action == Prev.Action) {
+ // Extend the range of the previous entry.
+ Prev.EndLabel = Site.EndLabel;
+ continue;
+ }
+ }
+
+ // Otherwise, create a new call-site.
+ CallSites.push_back(Site);
+ PreviousIsInvoke = true;
+ } else {
+ // Create a gap.
+ PreviousIsInvoke = false;
+ }
+ }
+ }
+ // If some instruction between the previous try-range and the end of the
+ // function may throw, create a call-site entry with no landing pad for the
+ // region following the try-range.
+ if (SawPotentiallyThrowing) {
+ CallSiteEntry Site = {LastLabel, 0, 0, 0};
+ CallSites.push_back(Site);
+ }
+