Implements TARGET_MEMTAG_CAN_TAG_ADDRESSES and TARGET_MEMTAG_TAG_BITSIZE
for the RISC-V back end, allowing -fsanitize=hwaddress if the target
machine supports the pointer masking extension.
------
gcc/ChangeLog:
* config/riscv/riscv.cc (riscv_can_tag_addresses): New function.
(RISCV_HWASAN_TAG_SIZE): New definition.
(riscv_memtag_tag_bitsize): New function.
(TARGET_MEMTAG_CAN_TAG_ADDRESSES): New definition.
(TARGET_MEMTAG_TAG_BITSIZE): Likewise.
Signed-off-by: Maximilian Ciric <[email protected]>
---
gcc/config/riscv/riscv.cc | 38 ++++++++++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)
diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
index 949616a63..f23690d03 100644
--- a/gcc/config/riscv/riscv.cc
+++ b/gcc/config/riscv/riscv.cc
@@ -16415,6 +16415,38 @@ riscv_prefetch_offset_address_p (rtx x, machine_mode
mode)
return true;
}
+
+/* Implement TARGET_MEMTAG_CAN_TAG_ADDRESSES.
+ * Enables -fsanitize=hwaddress if true. */
+
+bool
+riscv_can_tag_addresses ()
+{
+ /* Tagging is possible when a pointer masking extension is available. */
+ bool target_has_pointer_masking_p = TARGET_SMMPM
+ || TARGET_SMNPM
+ || TARGET_SSNPM
+ || TARGET_SSPM
+ || TARGET_SUPM;
+ return TARGET_64BIT && target_has_pointer_masking_p;
+}
+
+
+/* libsanitizer expects 8 tag bits. */
+
+#define RISCV_HWASAN_TAG_SIZE 8
+
+
+/* Implement TARGET_MEMTAG_TAG_BITSIZE.
+ * Communicates how many unused pointer bits are used for tagging. */
+
+unsigned char
+riscv_memtag_tag_bitsize ()
+{
+ return RISCV_HWASAN_TAG_SIZE;
+}
+
+
/* Initialize the GCC target structure. */
#undef TARGET_ASM_ALIGNED_HI_OP
#define TARGET_ASM_ALIGNED_HI_OP "\t.half\t"
@@ -16834,6 +16866,12 @@ riscv_prefetch_offset_address_p (rtx x, machine_mode
mode)
#define TARGET_GET_FUNCTION_VERSIONS_DISPATCHER \
riscv_get_function_versions_dispatcher
+#undef TARGET_MEMTAG_CAN_TAG_ADDRESSES
+#define TARGET_MEMTAG_CAN_TAG_ADDRESSES riscv_can_tag_addresses
+
+#undef TARGET_MEMTAG_TAG_BITSIZE
+#define TARGET_MEMTAG_TAG_BITSIZE riscv_memtag_tag_bitsize
+
#undef TARGET_DOCUMENTATION_NAME
#define TARGET_DOCUMENTATION_NAME "RISC-V"
--
2.34.1
