glibc/sysdeps/powerpc/ifunc-sel.h
Aurelien Jarno ee71e5b6dd powerpc: fix ifunc-sel.h with GCC 6
On 32-bit PowerPC GCC 6 always saves the PIC register on the stack in
the prologue and adjust the stack in the epilogue. It is therefore not
possible anymore to just exit the function in the inline asm code,
otherwise it corrupts the stack pointer. This causes the following tests
to fail when using GCC 6:

FAIL: elf/ifuncmain1
FAIL: elf/ifuncmain1pic
FAIL: elf/ifuncmain1picstatic
FAIL: elf/ifuncmain1pie
FAIL: elf/ifuncmain1staticpic
FAIL: elf/ifuncmain1staticpie
FAIL: elf/ifuncmain1vis
FAIL: elf/ifuncmain1vispic
FAIL: elf/ifuncmain1vispie
FAIL: elf/ifuncmain2pic
FAIL: elf/ifuncmain2picstatic
FAIL: elf/ifuncmain3
FAIL: elf/ifuncmain4picstatic
FAIL: elf/ifuncmain5
FAIL: elf/ifuncmain5picstatic
FAIL: elf/ifuncmain5staticpic

The solution is to replace the beqlr instructions by a beq to the end
of the inline asm code. This fixes all the above failures.

ChangeLog:
	* sysdeps/powerpc/ifunc-sel.h (ifunc_sel): Replace beqlr instructions
	by beq instructions jumping to the end of the function.
2016-08-03 00:22:44 +02:00

48 lines
1.0 KiB
C

/* Used by the elf ifunc tests. */
#ifndef ELF_IFUNC_SEL_H
#define ELF_IFUNC_SEL_H 1
extern int global;
static inline void *
ifunc_sel (int (*f1) (void), int (*f2) (void), int (*f3) (void))
{
register void *ret __asm__ ("r3");
__asm__ ("mflr 12\n\t"
"bcl 20,31,1f\n"
"1:\tmflr 11\n\t"
"mtlr 12\n\t"
"addis 12,11,global-1b@ha\n\t"
"lwz 12,global-1b@l(12)\n\t"
"addis %0,11,%2-1b@ha\n\t"
"addi %0,%0,%2-1b@l\n\t"
"cmpwi 12,1\n\t"
"beq 2f\n\t"
"addis %0,11,%3-1b@ha\n\t"
"addi %0,%0,%3-1b@l\n\t"
"cmpwi 12,-1\n\t"
"beq 2f\n\t"
"addis %0,11,%4-1b@ha\n\t"
"addi %0,%0,%4-1b@l\n\t"
"2:"
: "=r" (ret)
: "X" (&global), "X" (f1), "X" (f2), "X" (f3));
return ret;
}
static inline void *
ifunc_one (int (*f1) (void))
{
register void *ret __asm__ ("r3");
__asm__ ("mflr 12\n\t"
"bcl 20,31,1f\n"
"1:\tmflr %0\n\t"
"mtlr 12\n\t"
"addis %0,%0,%1-1b@ha\n\t"
"addi %0,%0,%1-1b@l"
: "=r" (ret)
: "X" (f1));
return ret;
}
#endif