Jovan Dmitrovic <jovan.dmitro...@syrmia.com> 于2023年6月6日周二 18:29写道: > > I suppose that it is possible to check assembly. >
Great. > Following is part of diff before and after my patch: > > 29,32c29,32 > < sd $6,0($2) > < sd $7,8($2) > < sd $8,16($2) > < sd $9,24($2) > --- > > sd $5,0($2) > > sd $6,8($2) > > sd $7,16($2) > > sd $8,24($2) > 63,66c63,66 > < sd $6,0($2) > < sd $7,8($2) > < sd $8,16($2) > < sd $9,24($2) > --- > > sd $5,0($2) > > sd $6,8($2) > > sd $7,16($2) > > sd $8,24($2) > 138,141c138,141 > < ld $6,64($16) > < ld $7,72($16) > < ld $8,80($16) > < ld $9,88($16) > --- > > ld $5,64($16) > > ld $6,72($16) > > ld $7,80($16) > > ld $8,88($16) > 148,151c148,151 > < ld $6,64($16) > < ld $7,72($16) > < ld $8,80($16) > < ld $9,88($16) > --- > > ld $5,64($16) > > ld $6,72($16) > > ld $7,80($16) > > ld $8,88($16) > 167,170c167,170 > < ld $6,0($16) > < ld $7,8($16) > < ld $8,16($16) > < ld $9,24($16) > --- > > ld $5,0($16) > > ld $6,8($16) > > ld $7,16($16) > > ld $8,24($16) > > What my patch effectively does it rearranges the data in > registers when invoking a function. I don't know whether > writing this testcase as an assembly check would make sense, > because that would make the testcase much less readable. I prefer an assembly check, because the test can be used even for cross building. It is not required, I guess. > ________________________________________ > From: YunQiang Su <wzss...@gmail.com> > Sent: Wednesday, May 31, 2023 12:05 PM > To: Jovan Dmitrovic > Cc: gcc-patches@gcc.gnu.org; Djordje Todorovic > Subject: Re: [PATCH] mips: Fix overaligned function arguments [PR109435] > > Jovan Dmitrovic <jovan.dmitro...@syrmia.com> 于2023年5月29日周一 19:00写道: > > > > This patch changes alignment for typedef types when passed as > > arguments, making the alignment equal to the alignment of > > original (aliased) types. > > > > This change makes it impossible for a typedef type to have > > alignment that is less than its size. > > > > Signed-off-by: Jovan Dmitrovic <jovan.dmitro...@syrmia.com> > > > > gcc/ChangeLog: > > PR target/109435 > > * config/mips/mips.cc (mips_function_arg_alignment): Returns > > the alignment of function argument. In case of typedef type, > > it returns the aligment of the aliased type. > > (mips_function_arg_boundary): Relocated calculation of the > > aligment of function arguments. > > > > gcc/testsuite/ChangeLog: > > PR target/109435 > > * gcc.target/mips/align-1.c: New test. > > --- > > gcc/config/mips/mips.cc | 18 +++++++++++++- > > gcc/testsuite/gcc.target/mips/align-1.c | 33 +++++++++++++++++++++++++ > > 2 files changed, 50 insertions(+), 1 deletion(-) > > create mode 100644 gcc/testsuite/gcc.target/mips/align-1.c > > > > diff --git a/gcc/config/mips/mips.cc b/gcc/config/mips/mips.cc > > index ca822758b41..2019b7cd7d9 100644 > > --- a/gcc/config/mips/mips.cc > > +++ b/gcc/config/mips/mips.cc > > @@ -6190,6 +6190,22 @@ mips_arg_partial_bytes (cumulative_args_t cum, const > > function_arg_info &arg) > > return info.stack_words > 0 ? info.reg_words * UNITS_PER_WORD : 0; > > } > > > > +/* Given MODE and TYPE of a function argument, return the alignment in > > + bits. In case of typedef, alignment of its original type is > > + used. */ > > + > > +static unsigned int > > +mips_function_arg_alignment (machine_mode mode, const_tree type) > > +{ > > + if (!type) > > + return GET_MODE_ALIGNMENT (mode); > > + > > + if (is_typedef_decl (TYPE_NAME (type))) > > + type = DECL_ORIGINAL_TYPE (TYPE_NAME (type)); > > + > > + return TYPE_ALIGN (type); > > +} > > + > > /* Implement TARGET_FUNCTION_ARG_BOUNDARY. Every parameter gets at > > least PARM_BOUNDARY bits of alignment, but will be given anything up > > to STACK_BOUNDARY bits if the type requires it. */ > > @@ -6198,8 +6214,8 @@ static unsigned int > > mips_function_arg_boundary (machine_mode mode, const_tree type) > > { > > unsigned int alignment; > > + alignment = mips_function_arg_alignment (mode, type); > > > > - alignment = type ? TYPE_ALIGN (type) : GET_MODE_ALIGNMENT (mode); > > if (alignment < PARM_BOUNDARY) > > alignment = PARM_BOUNDARY; > > if (alignment > STACK_BOUNDARY) > > diff --git a/gcc/testsuite/gcc.target/mips/align-1.c > > b/gcc/testsuite/gcc.target/mips/align-1.c > > new file mode 100644 > > index 00000000000..816751b8099 > > --- /dev/null > > +++ b/gcc/testsuite/gcc.target/mips/align-1.c > > @@ -0,0 +1,33 @@ > > +/* Check that typedef alignment does not affect passing of function > > + parameters. */ > > +/* { dg-do run { target { "mips*-*-linux*" } } } */ > > Is it possible to check the result with something like > scan-assembler > scan-assembler-not > instead of real running? > > > + > > +#include <assert.h> > > + > > +typedef struct ui8 > > +{ > > + unsigned v[8]; > > +} uint8 __attribute__ ((aligned(64))); > > + > > +unsigned > > +callee (int x, uint8 a) > > +{ > > + return a.v[0]; > > +} > > + > > +uint8 > > +identity (uint8 in) > > +{ > > + return in; > > +} > > + > > +int > > +main (void) > > +{ > > + uint8 vec = {{1, 2, 3, 4, 5, 6, 7, 8}}; > > + uint8 temp = identity (vec); > > + unsigned temp2 = callee (1, identity (vec)); > > + assert (callee (1, temp) == 1); > > + assert (temp2 == 1); > > + return 0; > > +} > > -- > > 2.34.1 > > -- YunQiang Su