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Update gcc6809 patch to fix an ICE. Add new gcc6809 patch with a fix to an internal compiler error reported by Tormod Volden. It seems whoever created the offending instruction patterns didn't fully understand the instruction contraints system and likely got away with it due to characteristics of the instruction generator in previous versions of gcc. Alas, it causes problems now so unless someone has a brilliant idea how to make it work, addhi_mem_1 and addhi_mem_minus1 have to go. Fortunately, the compiler is smart enough to use an alternate strategy all on its own.
author William Astle <lost@l-w.ca>
date Sun, 27 Mar 2016 21:46:18 -0600
parents b4d0eafc5bfe
children 3832a68d83ef
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416:b4d0eafc5bfe 417:d7b7004b0883
130 130
131 This is identical to the -3 version except it fixes a code generation bug 131 This is identical to the -3 version except it fixes a code generation bug
132 that showed up under optimization. It would result in the sense of a branch 132 that showed up under optimization. It would result in the sense of a branch
133 following a subtraction being inverted for whatever reason. This change 133 following a subtraction being inverted for whatever reason. This change
134 seems to fix that. 134 seems to fix that.
135
136 gcc6809lw-4.6.4-5.patch
137
138 This is the same as the -4 version except it removes two instruction
139 patterns that gcc was choosing to use in cases where they simply did not
140 apply and, thus, it was getting confused and leading to an ICE. These
141 patterns were a useful optmization for incrementing and decrementing 16 bit
142 values in memory but if the compiler core is going to select them in cases
143 where it really isn't an increment or decrement in place, the patterns are
144 not useful. The resulting code is slightly less good than it could be under
145 -Os but it's still correct.
146