<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW --- - Regression: Crash in 3Dmark2001" href="https://bugs.freedesktop.org/show_bug.cgi?id=82828#c6">Comment # 6</a> on <a class="bz_bug_link bz_status_NEW " title="NEW --- - Regression: Crash in 3Dmark2001" href="https://bugs.freedesktop.org/show_bug.cgi?id=82828">bug 82828</a> from <a class="email" href="mailto:cwabbott0@gmail.com" title="Connor Abbott <cwabbott0@gmail.com>"> Connor Abbott</a> <pre>(In reply to <a href="show_bug.cgi?id=82828#c5">comment #5</a>) > Created <a href="attachment.cgi?id=105451" name="attach_105451" title="full backtrace from piglit crash">attachment 105451</a> <a href="attachment.cgi?id=105451&action=edit" title="full backtrace from piglit crash">[details]</a> > full backtrace from piglit crash > > (In reply to <a href="show_bug.cgi?id=82828#c4">comment #4</a>) > > All the crashes are in the same place, right? > > > > Can you run it under gdb and print out n2 and the contents of > > g->nodes[n].adjacency_list (it's an array with g->nodes[n].adjacency_count > > elements) after the segfault? How about the former before the ra_simplify() > > call in the ra_allocate() call that's segfaulting? (If you don't know how to > > do this, see > > <a href="http://stackoverflow.com/questions/2956889/how-to-set-a-counter-for-a-gdb">http://stackoverflow.com/questions/2956889/how-to-set-a-counter-for-a-gdb</a>- > > breakpoint) > > > > I'm guessing that it's segfaulting because n2 is some bogus value. n2 comes > > from the adjacency_list, which is something generated before the allocator > > actually runs by code I didn't touch and then never modified afterward, and > > the code that's segfaulting wasn't modified by the commit in question, so > > the two most likely options I see are that either this is exposing a bug > > somewhere else (like in r300g) or the new ra_simplify() is somehow > > corrupting the adjacency_list. I don't know how r300g sets up the register > > conflicts and register classes, though, so I can't guess why it works fine > > on i965 but fails for r300g. > > OK, so not sure if I know what I'm doing but selecting one random crashing > piglit test > > /bin/shader_runner tests/shaders/glsl-fs-loop-continue.shader_test -auto > > Program received signal SIGSEGV, Segmentation fault. > 0xb76391a9 in ra_select (g=0x80c2058) at > ../../src/mesa/program/register_allocate.c:525 > 525 BITSET_TEST(g->regs->regs[r].conflicts, g->nodes[n2].reg)) { > > print n2 > $2 = 0 > > print n > $7 = 1 > > print g->nodes[n].adjacency_count > $1 = 3 > > print g->nodes[n].adjacency_list > $3 = (unsigned int *) 0x80c1b58 > > print g->nodes[n].adjacency_list[0] > $4 = 1 > > print g->nodes[n].adjacency_list[1] > $5 = 0 > > print g->nodes[n].adjacency_list[2] > $6 = 2 > > full backtrace attached. Can you print out the value of g->nodes[n2].reg? I think it may be NO_REG (0xffffffff), even though it shouldn't be (if a node is not on the stack, then it's supposed to be assigned a register already). (In reply to <a href="show_bug.cgi?id=82828#c5">comment #5</a>) > Created <a href="attachment.cgi?id=105451" name="attach_105451" title="full backtrace from piglit crash">attachment 105451</a> <a href="attachment.cgi?id=105451&action=edit" title="full backtrace from piglit crash">[details]</a> > full backtrace from piglit crash > > (In reply to <a href="show_bug.cgi?id=82828#c4">comment #4</a>) > > All the crashes are in the same place, right? > > > > Can you run it under gdb and print out n2 and the contents of > > g->nodes[n].adjacency_list (it's an array with g->nodes[n].adjacency_count > > elements) after the segfault? How about the former before the ra_simplify() > > call in the ra_allocate() call that's segfaulting? (If you don't know how to > > do this, see > > <a href="http://stackoverflow.com/questions/2956889/how-to-set-a-counter-for-a-gdb">http://stackoverflow.com/questions/2956889/how-to-set-a-counter-for-a-gdb</a>- > > breakpoint) > > > > I'm guessing that it's segfaulting because n2 is some bogus value. n2 comes > > from the adjacency_list, which is something generated before the allocator > > actually runs by code I didn't touch and then never modified afterward, and > > the code that's segfaulting wasn't modified by the commit in question, so > > the two most likely options I see are that either this is exposing a bug > > somewhere else (like in r300g) or the new ra_simplify() is somehow > > corrupting the adjacency_list. I don't know how r300g sets up the register > > conflicts and register classes, though, so I can't guess why it works fine > > on i965 but fails for r300g. > > OK, so not sure if I know what I'm doing but selecting one random crashing > piglit test > > /bin/shader_runner tests/shaders/glsl-fs-loop-continue.shader_test -auto > > Program received signal SIGSEGV, Segmentation fault. > 0xb76391a9 in ra_select (g=0x80c2058) at > ../../src/mesa/program/register_allocate.c:525 > 525 BITSET_TEST(g->regs->regs[r].conflicts, g->nodes[n2].reg)) { > > print n2 > $2 = 0 > > print n > $7 = 1 > > print g->nodes[n].adjacency_count > $1 = 3 > > print g->nodes[n].adjacency_list > $3 = (unsigned int *) 0x80c1b58 > > print g->nodes[n].adjacency_list[0] > $4 = 1 > > print g->nodes[n].adjacency_list[1] > $5 = 0 > > print g->nodes[n].adjacency_list[2] > $6 = 2 > > full backtrace attached.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> </ul> </body> </html>