[Bug target/34501] The vector cost model does not seem suited for Intel Core2Duo

["howarth at nitro dot med dot uc dot edu" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #4 from howarth at nitro dot med dot uc dot edu  2010-05-09 19:38 -------
With gcc-4.5.0 built as...

Using built-in specs.
COLLECT_GCC=gcc-4
COLLECT_LTO_WRAPPER=/sw/lib/gcc4.5/libexec/gcc/x86_64-apple-darwin10.3.0/4.5.0/lto-wrapper
Target: x86_64-apple-darwin10.3.0
Configured with: ../gcc-4.5.0/configure --prefix=/sw --prefix=/sw/lib/gcc4.5
--mandir=/sw/share/man --infodir=/sw/lib/gcc4.5/info
--enable-languages=c,c++,fortran,objc,obj-c++,java --with-gmp=/sw
--with-libiconv-prefix=/sw --with-ppl=/sw --with-cloog=/sw --with-mpc=/sw
--with-system-zlib --x-includes=/usr/X11R6/include --x-libraries=/usr/X11R6/lib
--program-suffix=-fsf-4.5
Thread model: posix
gcc version 4.5.0 (GCC) 

I get the following from...

$ touch t.cc
$ gcc -fverbose-asm t.cc -S

more t.s
# GNU C++ (GCC) version 4.5.0 (x86_64-apple-darwin10.3.0)
#       compiled by GNU C version 4.5.0, GMP version 4.3.1, MPFR version
2.4.2-p3, MPC version 0.8
# GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
# options passed:  -D__DYNAMIC__ t.cc -fPIC -mmacosx-version-min=10.6.3
# -mtune=generic -fverbose-asm
# options enabled:  -fPIC -falign-loops -fargument-alias
# -fasynchronous-unwind-tables -fauto-inc-dec -fbranch-count-reg -fcommon
# -fdelete-null-pointer-checks -fearly-inlining
# -feliminate-unused-debug-types -fexceptions -ffunction-cse -fgcse-lm
# -fident -finline-functions-called-once -fira-share-save-slots
# -fira-share-spill-slots -fivopts -fkeep-static-consts
# -fleading-underscore -fmerge-debug-strings -fmove-loop-invariants
# -fpeephole -freg-struct-return -fsched-critical-path-heuristic
# -fsched-dep-count-heuristic -fsched-group-heuristic -fsched-interblock
# -fsched-last-insn-heuristic -fsched-rank-heuristic -fsched-spec
# -fsched-spec-insn-heuristic -fsched-stalled-insns-dep -fshow-column
# -fsigned-zeros -fsplit-ivs-in-unroller -ftrapping-math -ftree-cselim
# -ftree-forwprop -ftree-loop-im -ftree-loop-ivcanon -ftree-loop-optimize
# -ftree-parallelize-loops= -ftree-phiprop -ftree-pta -ftree-reassoc
# -ftree-scev-cprop -ftree-slp-vectorize -ftree-vect-loop-version
# -funit-at-a-time -funwind-tables -fvect-cost-model -fverbose-asm
# -fzero-initialized-in-bss -gstrict-dwarf -m128bit-long-double -m64
# -m80387 -maccumulate-outgoing-args -malign-stringops -mfancy-math-387
# -mfp-ret-in-387 -mfused-madd -mieee-fp -mmmx -mno-sse4 -mpush-args
# -mred-zone -msse -msse2 -msse3

which shows that -mtune was set to generic for that release. I'll double check
with current gcc trunk but now suspect it has been changed to core2. 


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34501