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From: Vineet Gupta <vineetg@rivosinc.com>
To: gcc@gcc.gnu.org
Cc: Aldy Hernandez <aldyh@redhat.com>,
	Jeff Law <jeffreyalaw@gmail.com>,
	Philipp Tomsich <philipp.tomsich@vrull.eu>,
	gnu-toolchain <gnu-toolchain@rivosinc.com>
Subject: -Ofast/-ffast-math and SPEC 511.pov miscompilation with gcc 13.0
Date: Thu, 2 Feb 2023 15:38:05 -0800	[thread overview]
Message-ID: <78f4bcde-74ac-428f-99fe-a6193c52362e@rivosinc.com> (raw)

Hi,

I've noticed SPEC 2017, 511.pov failing for RV64 on bleeding edge gcc.
This is with -Ofast -march=rv64gcv_zba_zbb_zbc_zbs.
Problem also happens with -O3 -ffast-math (and goes away with fast-math 
removed)

I've bisected it to b7fd7fb50111 ("frange: drop endpoints to min/max 
representable numbers for -ffinite-math-only")
With that commit evrp is eliding a bunch of if conditions as they 
pertain to inf (in code snippet below, it elides code corresponding to 
lines 1401-1418 with line 1417 being elided causing the failure).

I think I know the answer, but  just wanted to confirm if that is the 
intended behavior given -Ofast / -ffast-math

Thx,
-Vineet


|New->Angle = __builtin_huge_val(); ||||switch(New->Type) ||{ ||... 
||1246: if(Parse_Camera_Mods(New) == false) ||EXIT ||... ||} ||||1401: 
if (New->Up[X] == ||||__builtin_huge_val|()|) { ... } 1417: if 
(New->Angle != |||__builtin_huge_val|()) ||{ ||1419: if ((New->Type == 
PERSPECTIVE_CAMERA) |||

             reply	other threads:[~2023-02-02 23:38 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-02-02 23:38 Vineet Gupta [this message]
2023-02-02 23:43 ` Vineet Gupta
2023-02-03  7:36 ` Richard Biener
2023-02-03 18:47   ` Vineet Gupta
2023-02-03 18:59     ` Richard Biener

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