From 30c1ba4834a9666ef5536a35c445cd8e91fcd0f5 Mon Sep 17 00:00:00 2001 From: Andrea Di Biagio Date: Tue, 13 Mar 2018 15:22:13 +0000 Subject: [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 --- llvm/lib/MC/MCSchedule.cpp | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'llvm/lib/MC/MCSchedule.cpp') diff --git a/llvm/lib/MC/MCSchedule.cpp b/llvm/lib/MC/MCSchedule.cpp index f3919427bf0..653049cc267 100644 --- a/llvm/lib/MC/MCSchedule.cpp +++ b/llvm/lib/MC/MCSchedule.cpp @@ -12,6 +12,7 @@ //===----------------------------------------------------------------------===// #include "llvm/MC/MCSchedule.h" +#include "llvm/MC/MCSubtargetInfo.h" #include using namespace llvm; @@ -32,3 +33,19 @@ const MCSchedModel MCSchedModel::Default = {DefaultIssueWidth, 0, 0, nullptr}; + +int MCSchedModel::computeInstrLatency(const MCSubtargetInfo &STI, + const MCSchedClassDesc &SCDesc) { + int 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); + // Early exit if we found an invalid latency. + if (WLEntry->Cycles < 0) + return WLEntry->Cycles; + Latency = std::max(Latency, static_cast(WLEntry->Cycles)); + } + return Latency; +} -- cgit v1.2.3