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-rw-r--r--include/elf/ppc64.h47
1 files changed, 47 insertions, 0 deletions
diff --git a/include/elf/ppc64.h b/include/elf/ppc64.h
index 1121649..d3cfdfb 100644
--- a/include/elf/ppc64.h
+++ b/include/elf/ppc64.h
@@ -180,6 +180,53 @@ END_RELOC_NUMBERS (R_PPC64_max)
0 for unspecified or not using any features affected by the differences. */
#define EF_PPC64_ABI 3
+/* The ELFv2 ABI uses three bits in the symbol st_other field of a
+ function definition to specify the number of instructions between a
+ function's global entry point and local entry point.
+ The global entry point is used when it is necessary to set up the
+ toc pointer (r2) for the function. Callers must enter the global
+ entry point with r12 set to the global entry point address. On
+ return from the function, r2 may have a different value to that
+ which it had on entry.
+ The local entry point is used when r2 is known to already be valid
+ for the function. There is no requirement on r12 when using the
+ local entry point, and on return r2 will contain the same value as
+ at entry.
+ A value of zero in these bits means that the function has a single
+ entry point with no requirement on r12 or r2, and that on return r2
+ will contain the same value as at entry.
+ Values of one and seven are reserved. */
+#define STO_PPC64_LOCAL_BIT 5
+#define STO_PPC64_LOCAL_MASK (7 << STO_PPC64_LOCAL_BIT)
+
+// 3 bit other field to bytes.
+static inline unsigned int
+ppc64_decode_local_entry(unsigned int other)
+{
+ return ((1 << other) >> 2) << 2;
+}
+
+// bytes to field value.
+static inline unsigned int
+ppc64_encode_local_entry(unsigned int val)
+{
+ return (val >= 4 * 4
+ ? (val >= 8 * 4
+ ? (val >= 16 * 4 ? 6 : 5)
+ : 4)
+ : (val >= 2 * 4
+ ? 3
+ : (val >= 1 * 4 ? 2 : 0)));
+}
+
+/* st_other to number of bytes. */
+#define PPC64_LOCAL_ENTRY_OFFSET(other) \
+ ppc64_decode_local_entry (((other) & STO_PPC64_LOCAL_MASK) \
+ >> STO_PPC64_LOCAL_BIT)
+/* number of bytes to st_other. */
+#define PPC64_SET_LOCAL_ENTRY_OFFSET(val) \
+ ppc64_encode_local_entry (val) << STO_PPC64_LOCAL_BIT
+
/* Specify the start of the .glink section. */
#define DT_PPC64_GLINK DT_LOPROC