[MC] Move the instruction latency computation from TargetSchedModel to MCSchedModel.

The goal is to make the latency information accessible through the MCSchedModel
interface. This is particularly important for tools like llvm-mca that only have
access to the MCSchedModel API.

This partially fixes PR36676.
No functional change intended.

Differential Revision: https://reviews.llvm.org/D44383

llvm-svn: 327406

1 files changed, 1 insertions, 9 deletions

diff --git a/llvm/lib/CodeGen/TargetSchedule.cpp b/llvm/lib/CodeGen/TargetSchedule.cpp
index 7d636b126e0..432545bde1f 100644
--- a/llvm/lib/CodeGen/TargetSchedule.cpp
+++ b/llvm/lib/CodeGen/TargetSchedule.cpp
@@ -257,15 +257,7 @@ unsigned TargetSchedModel::computeOperandLatency(
 
 unsigned
 TargetSchedModel::computeInstrLatency(const MCSchedClassDesc &SCDesc) const {
-  unsigned Latency = 0;
-  for (unsigned DefIdx = 0, DefEnd = SCDesc.NumWriteLatencyEntries;
-       DefIdx != DefEnd; ++DefIdx) {
-    // Lookup the definition's write latency in SubtargetInfo.
-    const MCWriteLatencyEntry *WLEntry =
-      STI->getWriteLatencyEntry(&SCDesc, DefIdx);
-    Latency = std::max(Latency, capLatency(WLEntry->Cycles));
-  }
-  return Latency;
+  return capLatency(MCSchedModel::computeInstrLatency(*STI, SCDesc));
 }
 
 unsigned TargetSchedModel::computeInstrLatency(unsigned Opcode) const {