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-rw-r--r--binutils-2.25/gold/testsuite/ifunc-sel.h92
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diff --git a/binutils-2.25/gold/testsuite/ifunc-sel.h b/binutils-2.25/gold/testsuite/ifunc-sel.h
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+/* Used by the elf ifunc tests. */
+#ifndef ELF_IFUNC_SEL_H
+#define ELF_IFUNC_SEL_H 1
+
+extern int global;
+
+static inline __attribute__ ((always_inline)) void *
+ifunc_sel (int (*f1) (void), int (*f2) (void), int (*f3) (void))
+{
+#ifdef __powerpc__
+ /* When generating PIC, powerpc gcc loads the address of "global"
+ from the GOT, but the GOT may not have been relocated.
+ Similarly, "f1", "f2" and "f3" may be loaded from non-relocated
+ GOT entries.
+
+ There is NO WAY to make this ill conceived IFUNC misfeature
+ reliably work on targets that use a GOT for function or variable
+ addresses, short of implementing two passes over relocations in
+ ld.so, with ifunc relocations being applied after all other
+ relocations, globally.
+
+ Cheat. Don't use the GOT. Rely on this function being inlined
+ and calculate all variable and function addresses relative to pc.
+ Using the 'X' constraint is risky, but that's the only way to
+ make the asm here see the function names for %4, %5 and %6.
+ Sadly, powerpc64 gcc doesn't accept use of %3 here with 'X' for
+ some reason, so we expand it ourselves. */
+ register void *ret __asm__ ("r3");
+ void *temp1, *temp2;
+ __asm__ ("mflr %1\n\t"
+ "bcl 20,31,1f\n"
+ "1:\tmflr %2\n\t"
+ "mtlr %1\n\t"
+ "addis %1,%2,global-1b@ha\n\t"
+ "lwz %1,global-1b@l(%1)\n\t"
+ "addis %0,%2,%4-1b@ha\n\t"
+ "addi %0,%0,%4-1b@l\n\t"
+ "cmpwi %1,1\n\t"
+ "beqlr\n\t"
+ "addis %0,%2,%5-1b@ha\n\t"
+ "addi %0,%0,%5-1b@l\n\t"
+ "cmpwi %1,-1\n\t"
+ "beqlr\n\t"
+ "addis %0,%2,%6-1b@ha\n\t"
+ "addi %0,%0,%6-1b@l"
+ : "=&b" (ret), "=&b" (temp1), "=&b" (temp2)
+ : "X" (&global), "X" (f1), "X" (f2), "X" (f3));
+ return ret;
+#else
+ switch (global)
+ {
+ case 1:
+ return f1;
+ case -1:
+ return f2;
+ default:
+ return f3;
+ }
+#endif
+}
+
+static inline __attribute__ ((always_inline)) void *
+ifunc_one (int (*f1) (void))
+{
+#ifdef __powerpc__
+ /* As above, PIC may use an unrelocated GOT entry for f1.
+
+ Case study: ifuncmain6pie's shared library, ifuncmod6.so, wants
+ the address of "foo" in function get_foo(). So there is a GOT
+ entry for "foo" in ifuncmod6.so. ld.so relocates ifuncmod6.so
+ *before* ifuncmain6pie, and on finding "foo" to be STT_GNU_IFUNC,
+ calls this function with f1 set to "one". But the address of
+ "one" is loaded from ifuncmain6pie's GOT, which hasn't been
+ relocated yet.
+
+ Cheat as for ifunc-sel. */
+ register void *ret __asm__ ("r3");
+ void *temp;
+ __asm__ ("mflr %1\n\t"
+ "bcl 20,31,1f\n"
+ "1:\tmflr %0\n\t"
+ "mtlr %1\n\t"
+ "addis %0,%0,%2-1b@ha\n\t"
+ "addi %0,%0,%2-1b@l"
+ : "=&b" (ret), "=&r" (temp)
+ : "X" (f1));
+ return ret;
+#else
+ return f1;
+#endif
+}
+#endif