http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46296
Summary: Compiler causes assembler warning
Product: gcc
Version: 4.3.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: jswor...@qwest.net
Created attachment 22270
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22270
A pre-processed source file that exhibits the behavior
When the attached file is compiled for Itanium with -O2, the assembler emits
the following warning (obviously the file name varies):
/tmp/ccYZ8n8x.s: Assembler messages:
/tmp/ccYZ8n8x.s:804: Warning: Use of 'addl' may violate WAW dependency 'GR%, %
in 1 - 127' (impliedf), specific resource number is 34
/tmp/ccYZ8n8x.s:802: Warning: This is the location of the conflicting usage
Inspecting the generated code around the indicated line shows:
{ .mii
cmp4.eq p6, p7 = 0, r8
mov r1 = r49 ;;
(p7) mov r32 = r0
}
{ .mib
(p7) cmp.ne p16, p17 = r0, r0
(p7) addl r36 = -94, r0
(p7) br.cond.dptk .L11
} ;;
{ .mmi
adds r36=48,r12
mov r51=16
(p16) mov r34=r0
}
{ .mmi
(p17) mov r34=16;;
nop.m 0x0
mov r52=r36
}
{ .mib
nop.m 0x0
nop.m 0x0
br.call.sptk.many b0=s64_rand_gen
} ;;
Apparently, the assembler has lost any notion that p16 and p17, which are set
to reflect server == 1 and server != 1, respectively, are still mutually
exclusive after the conditional branch.
If the source file is changed to have a non-static or external declaration for
generate_rsa_key(), the error goes away.
