From: Joel Hestness <hestness@cs.wisc.edu>
Date: Sat, 19 Jan 2013 21:14:54 +0000 (-0600)
Subject: O3 IEW: Make incrWb and decrWb clearer
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=1429d2124406440946fbe80a6e9dfe1148f3af91;p=gem5.git

O3 IEW: Make incrWb and decrWb clearer

Move the increment/decrement of wbOutstanding outside of the comparison
in incrWb and decrWb in the IEW. This also fixes a compiler bug with gcc
4.4.7, which incorrectly optimizes "-- ==" as "-=".
---

diff --git a/src/cpu/o3/iew.hh b/src/cpu/o3/iew.hh
index 5adf32752..1213cf12b 100644
--- a/src/cpu/o3/iew.hh
+++ b/src/cpu/o3/iew.hh
@@ -213,7 +213,8 @@ class DefaultIEW
 
     void incrWb(InstSeqNum &sn)
     {
-        if (++wbOutstanding == wbMax)
+        ++wbOutstanding;
+        if (wbOutstanding == wbMax)
             ableToIssue = false;
         DPRINTF(IEW, "wbOutstanding: %i [sn:%lli]\n", wbOutstanding, sn);
         assert(wbOutstanding <= wbMax);
@@ -224,8 +225,9 @@ class DefaultIEW
 
     void decrWb(InstSeqNum &sn)
     {
-        if (wbOutstanding-- == wbMax)
+        if (wbOutstanding == wbMax)
             ableToIssue = true;
+        wbOutstanding--;
         DPRINTF(IEW, "wbOutstanding: %i [sn:%lli]\n", wbOutstanding, sn);
         assert(wbOutstanding >= 0);
 #ifdef DEBUG