[Bug tree-optimization/88240] Potential optimization bug: invalid pre-load of floating-point value could cause SIGFPE-underflow if value is integer

2019-03-26 Thread rguenth at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88240 Bug 88240 depends on bug 86554, which changed state. Bug 86554 Summary: [7 Regression] Incorrect code generation with signed/unsigned comparison https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86554 What|Removed

[Bug tree-optimization/88240] Potential optimization bug: invalid pre-load of floating-point value could cause SIGFPE-underflow if value is integer

2019-01-22 Thread rguenth at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88240 Richard Biener changed: What|Removed |Added Keywords||wrong-code

[Bug tree-optimization/88240] Potential optimization bug: invalid pre-load of floating-point value could cause SIGFPE-underflow if value is integer

2019-01-22 Thread patrickdepinguin at gmail dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88240 --- Comment #11 from Thomas De Schampheleire --- Any feedback? With the reduced testcase qemu is out of the picture. Do you agree that this is a bug in gcc?

[Bug tree-optimization/88240] Potential optimization bug: invalid pre-load of floating-point value could cause SIGFPE-underflow if value is integer

2018-12-06 Thread patrickdepinguin at gmail dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88240 --- Comment #10 from Thomas De Schampheleire --- I was able to further investigate and reduce the problem. Qemu is now out of the picture, I can reproduce the issue directly on a real CPU. All I need to do is enable the 'underflow' exception bit

[Bug tree-optimization/88240] Potential optimization bug: invalid pre-load of floating-point value could cause SIGFPE-underflow if value is integer

2018-11-29 Thread fw at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88240 --- Comment #9 from Florian Weimer --- (In reply to Thomas De Schampheleire from comment #6) > (In reply to Florian Weimer from comment #5) > > This is QEMU with TCG, right? It could be an i387 emulation bug. > > I don't think so. Isn't it so

[Bug tree-optimization/88240] Potential optimization bug: invalid pre-load of floating-point value could cause SIGFPE-underflow if value is integer

2018-11-28 Thread patrickdepinguin at gmail dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88240 --- Comment #8 from Thomas De Schampheleire --- To clarify the situation with underflow / denormal exception I will debug the issue again and inspect the corresponding registers. I'm not familiar with 'NaNs': is it a specific value that I can

[Bug tree-optimization/88240] Potential optimization bug: invalid pre-load of floating-point value could cause SIGFPE-underflow if value is integer

2018-11-28 Thread joseph at codesourcery dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88240 --- Comment #7 from joseph at codesourcery dot com --- As discussed, the load instructions should never raise underflow exceptions, and having traps enabled for the nonstandard denormal operand exception is clearly outside the scope of what

[Bug tree-optimization/88240] Potential optimization bug: invalid pre-load of floating-point value could cause SIGFPE-underflow if value is integer

2018-11-28 Thread patrickdepinguin at gmail dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88240 --- Comment #6 from Thomas De Schampheleire --- (In reply to Florian Weimer from comment #5) > (In reply to Thomas De Schampheleire from comment #4) > > When analyzing this problem with gdb, we looked at the floating-point status > > register

[Bug tree-optimization/88240] Potential optimization bug: invalid pre-load of floating-point value could cause SIGFPE-underflow if value is integer

2018-11-28 Thread fw at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88240 Florian Weimer changed: What|Removed |Added CC||fw at gcc dot gnu.org --- Comment #5

[Bug tree-optimization/88240] Potential optimization bug: invalid pre-load of floating-point value could cause SIGFPE-underflow if value is integer

2018-11-28 Thread patrickdepinguin at gmail dot com
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88240 --- Comment #4 from Thomas De Schampheleire --- (In reply to Uroš Bizjak from comment #2) > (In reply to Thomas De Schampheleire from comment #0) > > gcc 7.3.0 optimizes below code in a way that may cause a floating-point > > underflow (SIGFPE

[Bug tree-optimization/88240] Potential optimization bug: invalid pre-load of floating-point value could cause SIGFPE-underflow if value is integer

2018-11-28 Thread rguenth at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88240 Richard Biener changed: What|Removed |Added CC||rguenth at gcc dot gnu.org