| Message ID | VI1PR0801MB203191B1657765102CDA6A66FFB80@VI1PR0801MB2031.eurprd08.prod.outlook.com |
|---|---|
| State | New |
| Headers | show |
On 7/25/17 1:59 PM, Tamar Christina wrote: > Hi All, > > The new ARM options parser generates from the following entry > > begin cpu cortex-a55 > ... > architecture armv8.2-a+fp16+foo > option crypto add FP_ARMv8 CRYPTO > option dotprod add FP_ARMv8 FOO > option nofp remove ALL_FP > ... > end cpu cortex-a55 > > A list of all feature bits that using -mcpu=cortex-a55 > enabled and stores these in an array. The size of this array > is statically set to be isa_num_bits which is the last entry > in the isa_feature_bits enum. > > What this means is that there is an assumption that you can > never have more feature bits in this array than there are > features. Which is a reasonable assumption only if the entries > in the array are unique. > > The above example currently would add FP_ARMv8 three times. > FP_ARMv8 maps to the macro ISA_FP_ARMv8. Which when expanded > trivially exceeds the size of the array. > > This patch makes sure that when constructing the array we only > emit an a value once. The array is constructed between three > different sources which is where the duplications come in. > > Because we can't however look into the macros. When expended > they may still introduce duplicate bits. So this doesn't > completely fix the problem. Just makes it a bit less likely. > > Bootstrapped on arm-none-eabi and no issues. > > Ok for trunk? > > gcc/ > 2017-07-25 Tamar Christina <tamar.christina@arm.com> > > * config/arm/parsecpu.awk (all_cores): Remove duplicates. > Ok. Thanks for fixing this. regards Ramana
diff --git a/gcc/config/arm/parsecpu.awk b/gcc/config/arm/parsecpu.awk index 9d01e2cf992c9643534a7621e59e78041f8a1f9f..070d193b338ace0deb9aeb53a51796bfd633ade8 100644 --- a/gcc/config/arm/parsecpu.awk +++ b/gcc/config/arm/parsecpu.awk @@ -223,10 +223,39 @@ function gen_comm_data () { if (arch_opt_remove[feats[1],feats[m]] == "true") { fatal("cannot remove features from architecture specs") } - print " " arch_opt_isa[feats[1],feats[m]] "," + # The isa_features array that is being initialized here has a length + # of max isa_bit_num, which is the last entry in the enum. + # Logically this means that the number of features is implicitly + # never more than the number of feature bits we have. This is only + # true if we don't emit duplicates here. So keep track of which + # options we have already emitted so we don't emit them twice. + nopts = split (arch_opt_isa[feats[1],feats[m]], opts, ",") + for (i = 1; i <= nopts; i++) { + if (! (opts[i] in seen)) { + print " " opts[i] "," + seen[opts[i]] + } + } + } + if (cpus[n] in cpu_fpu) { + nopts = split (fpu_isa[cpu_fpu[cpus[n]]], opts, ",") + for (i = 1; i <= nopts; i++) { + if (! (opts[i] in seen)) { + print " " opts[i] "," + seen[opts[i]] + } + } + } + if (cpus[n] in cpu_isa) { + nopts = split (cpu_isa[cpus[n]], opts, ",") + for (i = 1; i <= nopts; i++) { + if (! (opts[i] in seen)) { + print " " opts[i] "," + seen[opts[i]] + } + } } - if (cpus[n] in cpu_fpu) print " " fpu_isa[cpu_fpu[cpus[n]]] "," - if (cpus[n] in cpu_isa) print " " cpu_isa[cpus[n]] "," + delete seen print " isa_nobit" print " }" print " },"