| Message ID | 53A19F20.7070703@arm.com |
|---|---|
| State | New |
| Headers | show |
On 18/06/14 15:16, Yufeng Zhang wrote: > Hi, > > This improves the robustness of the aapcs64 test framework for testing > function return ABI rules. It ensures the test facility functions now > able to see the exact content of return registers right at the moment > when a function returns. > > OK for trunk? OK once the issues with the comment are clarified. R. > > Thanks, > Yufeng > > gcc/testsuite > > Make the AAPCS64 function return tests more robust. > > * gcc.target/aarch64/aapcs64/abitest-2.h (saved_return_address): New > global variable. > (FUNC_VAL_CHECK): Update to call myfunc via the 'ret' instruction, > instead of calling sequentially in the C code. > * gcc.target/aarch64/aapcs64/abitest.S (LABEL_TEST_FUNC_RETURN): Store > saved_return_address to the stack frame where LR register was stored. > (saved_return_address): Declare weak. > > > patch > > > diff --git a/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest-2.h b/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest-2.h > index c56e7cc..c87fe9b 100644 > --- a/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest-2.h > +++ b/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest-2.h > @@ -5,6 +5,7 @@ > #include "validate_memory.h" > > void (*testfunc_ptr)(char* stack); > +unsigned long long saved_return_address; > > /* Helper macros to generate function name. Example of the function name: > func_return_val_1. */ > @@ -71,6 +72,17 @@ __attribute__ ((noinline)) type FUNC_NAME (id) (int i, double d, type t) \ > optimized away. Using i and d prevents \ > warnings about unused parameters. \ > */ \ > + /* We save and set up the LR register in a way that essentially \ > + inserts myfunc () between the returning of this function and the \ s/returning/return/ > + continueous execution of its caller. By doing this, myfunc () \ Typo: continueous. Do you mean continuing? > + can save and check the exact content of the registers that are \ > + used for the function return value. \ stray tab. > + The previous approach of sequentially calling myfunc right after \ > + this function does not guarantee myfunc see the exact register \ > + content, as compiler may emit code in between the two calls, \ Similarly. > + especially during the -O0 codegen. */ \ > + asm volatile ("mov %0, x30" : "=r" (saved_return_address)); \ > + asm volatile ("mov x30, %0" : : "r" ((unsigned long long) myfunc)); \ > return t; \ > } > #include TESTFILE > @@ -84,7 +96,8 @@ __attribute__ ((noinline)) type FUNC_NAME (id) (int i, double d, type t) \ > { \ > testfunc_ptr = TEST_FUNC_NAME(id); \ > FUNC_NAME(id) (0, 0.0, var); \ > - myfunc (); \ > + /* The above function implicitly calls myfunc () on its return, \ > + and the execution resumes from here after myfunc () finishes. */\ > } > > int main() > diff --git a/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest.S b/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest.S > index 86ce7be..68845fb 100644 > --- a/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest.S > +++ b/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest.S > @@ -50,6 +50,10 @@ LABEL_TEST_FUNC_RETURN: > add x9, x9, :lo12:testfunc_ptr > ldr x9, [x9, #0] > blr x9 // function return value test > + adrp x9, saved_return_address > + add x9, x9, :lo12:saved_return_address > + ldr x9, [x9, #0] > + str x9, [sp, #8] // Update the copy of LR reg saved on stack > LABEL_RET: > ldp x0, x30, [sp] > mov sp, x0 > @@ -57,3 +61,4 @@ LABEL_RET: > > .weak testfunc > .weak testfunc_ptr > +.weak saved_return_address >
diff --git a/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest-2.h b/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest-2.h index c56e7cc..c87fe9b 100644 --- a/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest-2.h +++ b/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest-2.h @@ -5,6 +5,7 @@ #include "validate_memory.h" void (*testfunc_ptr)(char* stack); +unsigned long long saved_return_address; /* Helper macros to generate function name. Example of the function name: func_return_val_1. */ @@ -71,6 +72,17 @@ __attribute__ ((noinline)) type FUNC_NAME (id) (int i, double d, type t) \ optimized away. Using i and d prevents \ warnings about unused parameters. \ */ \ + /* We save and set up the LR register in a way that essentially \ + inserts myfunc () between the returning of this function and the \ + continueous execution of its caller. By doing this, myfunc () \ + can save and check the exact content of the registers that are \ + used for the function return value. \ + The previous approach of sequentially calling myfunc right after \ + this function does not guarantee myfunc see the exact register \ + content, as compiler may emit code in between the two calls, \ + especially during the -O0 codegen. */ \ + asm volatile ("mov %0, x30" : "=r" (saved_return_address)); \ + asm volatile ("mov x30, %0" : : "r" ((unsigned long long) myfunc)); \ return t; \ } #include TESTFILE @@ -84,7 +96,8 @@ __attribute__ ((noinline)) type FUNC_NAME (id) (int i, double d, type t) \ { \ testfunc_ptr = TEST_FUNC_NAME(id); \ FUNC_NAME(id) (0, 0.0, var); \ - myfunc (); \ + /* The above function implicitly calls myfunc () on its return, \ + and the execution resumes from here after myfunc () finishes. */\ } int main() diff --git a/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest.S b/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest.S index 86ce7be..68845fb 100644 --- a/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest.S +++ b/gcc/testsuite/gcc.target/aarch64/aapcs64/abitest.S @@ -50,6 +50,10 @@ LABEL_TEST_FUNC_RETURN: add x9, x9, :lo12:testfunc_ptr ldr x9, [x9, #0] blr x9 // function return value test + adrp x9, saved_return_address + add x9, x9, :lo12:saved_return_address + ldr x9, [x9, #0] + str x9, [sp, #8] // Update the copy of LR reg saved on stack LABEL_RET: ldp x0, x30, [sp] mov sp, x0 @@ -57,3 +61,4 @@ LABEL_RET: .weak testfunc .weak testfunc_ptr +.weak saved_return_address