Message ID | 1345368480-8431-1-git-send-email-penberg@kernel.org (mailing list archive) |
---|---|
State | Mainlined, archived |
Headers | show |
On 08/19/2012 05:28 AM, Pekka Enberg wrote: > Jonathan Neuschäfer reports: > > A simple function like this will compile to the following llvm > bitcode: > > /* C */ > void func(void) { > return; > } > > /* LLVM */ > define i8 @func() { > L0: > ret void > } > > The return type of the function and the type in the return instruction > don't match. > > I found this inconsistency by running LLVM's bitcode validation on the > bitcode produced by sparse-llvm. > > Move 'void *' special-casing from sym_basetype_type() to sym_ptr_type() > to fix the issue. > > Reported by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> > Cc: Christopher Li <sparse@chrisli.org> > Cc: Jeff Garzik <jgarzik@redhat.com> > Cc: Linus Torvalds <torvalds@linux-foundation.org> > Signed-off-by: Pekka Enberg <penberg@kernel.org> > --- > sparse-llvm.c | 12 ++++++++++-- > validation/backend/void-return-type.c | 13 +++++++++++++ > 2 files changed, 23 insertions(+), 2 deletions(-) > create mode 100644 validation/backend/void-return-type.c > > diff --git a/sparse-llvm.c b/sparse-llvm.c > index e02e212..213d42d 100644 > --- a/sparse-llvm.c > +++ b/sparse-llvm.c > @@ -150,7 +150,13 @@ static LLVMTypeRef sym_union_type(LLVMModuleRef module, struct symbol *sym) > > static LLVMTypeRef sym_ptr_type(LLVMModuleRef module, struct symbol *sym) > { > - LLVMTypeRef type = symbol_type(module, sym->ctype.base_type); > + LLVMTypeRef type; > + > + /* 'void *' is treated like 'char *' */ > + if (is_void_type(sym->ctype.base_type)) > + type = LLVMInt8Type(); > + else > + type = symbol_type(module, sym->ctype.base_type); > > return LLVMPointerType(type, 0); > } > @@ -176,10 +182,12 @@ static LLVMTypeRef sym_basetype_type(struct symbol *sym) > } > } else { > switch (sym->bit_size) { > + case -1: > + ret = LLVMVoidType(); > + break; > case 1: > ret = LLVMInt1Type(); > break; > - case -1: /* 'void *' is treated like 'char *' */ > case 8: > ret = LLVMInt8Type(); > break; > diff --git a/validation/backend/void-return-type.c b/validation/backend/void-return-type.c > new file mode 100644 > index 0000000..b282fde > --- /dev/null > +++ b/validation/backend/void-return-type.c > @@ -0,0 +1,13 @@ > +static void foo(void) > +{ > +} > + > +static void *bar(void *p) > +{ > + return p; > +} > + ACK the code... would prefer that the first testcase included a "return;" just to be certain we get that right. Jeff -- To unsubscribe from this list: send the line "unsubscribe linux-sparse" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/sparse-llvm.c b/sparse-llvm.c index e02e212..213d42d 100644 --- a/sparse-llvm.c +++ b/sparse-llvm.c @@ -150,7 +150,13 @@ static LLVMTypeRef sym_union_type(LLVMModuleRef module, struct symbol *sym) static LLVMTypeRef sym_ptr_type(LLVMModuleRef module, struct symbol *sym) { - LLVMTypeRef type = symbol_type(module, sym->ctype.base_type); + LLVMTypeRef type; + + /* 'void *' is treated like 'char *' */ + if (is_void_type(sym->ctype.base_type)) + type = LLVMInt8Type(); + else + type = symbol_type(module, sym->ctype.base_type); return LLVMPointerType(type, 0); } @@ -176,10 +182,12 @@ static LLVMTypeRef sym_basetype_type(struct symbol *sym) } } else { switch (sym->bit_size) { + case -1: + ret = LLVMVoidType(); + break; case 1: ret = LLVMInt1Type(); break; - case -1: /* 'void *' is treated like 'char *' */ case 8: ret = LLVMInt8Type(); break; diff --git a/validation/backend/void-return-type.c b/validation/backend/void-return-type.c new file mode 100644 index 0000000..b282fde --- /dev/null +++ b/validation/backend/void-return-type.c @@ -0,0 +1,13 @@ +static void foo(void) +{ +} + +static void *bar(void *p) +{ + return p; +} + +/* + * check-name: void return type code generation + * check-command: ./sparsec -c $file -o tmp.o + */
Jonathan Neuschäfer reports: A simple function like this will compile to the following llvm bitcode: /* C */ void func(void) { return; } /* LLVM */ define i8 @func() { L0: ret void } The return type of the function and the type in the return instruction don't match. I found this inconsistency by running LLVM's bitcode validation on the bitcode produced by sparse-llvm. Move 'void *' special-casing from sym_basetype_type() to sym_ptr_type() to fix the issue. Reported by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Cc: Christopher Li <sparse@chrisli.org> Cc: Jeff Garzik <jgarzik@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Pekka Enberg <penberg@kernel.org> --- sparse-llvm.c | 12 ++++++++++-- validation/backend/void-return-type.c | 13 +++++++++++++ 2 files changed, 23 insertions(+), 2 deletions(-) create mode 100644 validation/backend/void-return-type.c