From 06b305bb342ac02b22b77050324864b3217e7482 Mon Sep 17 00:00:00 2001 From: Javier Bueno Date: Tue, 2 Apr 2019 23:39:06 +0200 Subject: [PATCH] mem-cache: Fix panic in Indirect Memory prefetcher Memory requests with a size non-power-of-two and less than 8 values were causing a panic, but there these should be allowed and ignored by the prefetcher. Change-Id: I86baa60058cc8a7f232d6ba5748d4c24a463c840 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17733 Reviewed-by: Daniel Carvalho Reviewed-by: Nikos Nikoleris Maintainer: Nikos Nikoleris --- src/mem/cache/prefetch/indirect_memory.cc | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/src/mem/cache/prefetch/indirect_memory.cc b/src/mem/cache/prefetch/indirect_memory.cc index 393958c57..d49652fa8 100644 --- a/src/mem/cache/prefetch/indirect_memory.cc +++ b/src/mem/cache/prefetch/indirect_memory.cc @@ -108,6 +108,7 @@ IndirectMemoryPrefetcher::calculatePrefetch(const PrefetchInfo &pfi, if (!miss && !pfi.isWrite() && pfi.getSize() <= 8) { int64_t index = 0; + bool read_index = true; switch(pfi.getSize()) { case sizeof(uint8_t): index = pfi.get(byteOrder); @@ -122,14 +123,15 @@ IndirectMemoryPrefetcher::calculatePrefetch(const PrefetchInfo &pfi, index = pfi.get(byteOrder); break; default: - panic("Invalid access size\n"); + // Ignore non-power-of-two sizes + read_index = false; } - if (!pt_entry->enabled) { + if (read_index && !pt_entry->enabled) { // Not enabled (no pattern detected in this stream), // add or update an entry in the pattern detector and // start tracking misses allocateOrUpdateIPDEntry(pt_entry, index); - } else { + } else if (read_index) { // Enabled entry, update the index pt_entry->index = index; if (!pt_entry->increasedIndirectCounter) { -- 2.30.2