[PATCH v2] LoongArch: Fix pr106828 by define hook TARGET_ASAN_SHADOW_OFFSET in loongarch backend.

[Lulu Cheng]

Sorry, asan shadow offset is wrong in v1.

In the file asan_mapping.h line 207:
        #    define ASAN_SHADOW_OFFSET_CONST 0x0000400000000000

So it's should be 1<<46.

------------------------------------
gcc/ChangeLog:

        PR target/106828
        * config/loongarch/loongarch.cc (loongarch_asan_shadow_offset): New.
        (TARGET_ASAN_SHADOW_OFFSET): New.

gcc/testsuite/ChangeLog:

        PR target/106828
        * g++.target/loongarch/pr106828.C: New test.
---
 gcc/config/loongarch/loongarch.cc             | 13 +++++++++++++
 gcc/testsuite/g++.target/loongarch/pr106828.C |  4 ++++
 2 files changed, 17 insertions(+)
 create mode 100644 gcc/testsuite/g++.target/loongarch/pr106828.C

diff --git a/gcc/config/loongarch/loongarch.cc 
b/gcc/config/loongarch/loongarch.cc
index 10acf06ef79..424fa4487f8 100644
--- a/gcc/config/loongarch/loongarch.cc
+++ b/gcc/config/loongarch/loongarch.cc
@@ -6471,6 +6471,16 @@ loongarch_use_anchors_for_symbol_p (const_rtx symbol)
   return default_use_anchors_for_symbol_p (symbol);
 }
 
+/* Implement the TARGET_ASAN_SHADOW_OFFSET hook.  */
+
+static unsigned HOST_WIDE_INT
+loongarch_asan_shadow_offset (void)
+{
+  /* We only have libsanitizer support for LOONGARCH64 at present.
+     This value is taken from the file libsanitizer/asan/asan_mappint.h.  */
+  return TARGET_64BIT ? (HOST_WIDE_INT_1 << 46) : 0;
+}
+
 /* Initialize the GCC target structure.  */
 #undef TARGET_ASM_ALIGNED_HI_OP
 #define TARGET_ASM_ALIGNED_HI_OP "\t.half\t"
@@ -6665,6 +6675,9 @@ loongarch_use_anchors_for_symbol_p (const_rtx symbol)
 #undef  TARGET_USE_ANCHORS_FOR_SYMBOL_P
 #define TARGET_USE_ANCHORS_FOR_SYMBOL_P loongarch_use_anchors_for_symbol_p
 
+#undef TARGET_ASAN_SHADOW_OFFSET
+#define TARGET_ASAN_SHADOW_OFFSET loongarch_asan_shadow_offset
+
 struct gcc_target targetm = TARGET_INITIALIZER;
 
 #include "gt-loongarch.h"
diff --git a/gcc/testsuite/g++.target/loongarch/pr106828.C 
b/gcc/testsuite/g++.target/loongarch/pr106828.C
new file mode 100644
index 00000000000..190c1db715f
--- /dev/null
+++ b/gcc/testsuite/g++.target/loongarch/pr106828.C
@@ -0,0 +1,4 @@
+/* { dg-do-preprocess } */
+/* { dg-options "-mabi=lp64d -fsanitize=address" } */
+
+/* Tests whether the compiler supports compile option '-fsanitize=address'.  */
-- 
2.31.1