Port address sanitizer to LoongArch

Depends on D129371.

It survived all GCC ASan tests.

Changes are trivial and mostly "borrowed" RISC-V logics, except that a different SHADOW_OFFSET is used.

Reviewed By: SixWeining, MaskRay, XiaodongLoong

Differential Revision: https://reviews.llvm.org/D129418

compiler-rt/cmake/Modules/AllSupportedArchDefs.cmake

@@ -27,7 +27,8 @@ set(ALL_SANITIZER_COMMON_SUPPORTED_ARCH ${X86} ${X86_64} ${PPC64} ${RISCV64}
     ${ARM32} ${ARM64} ${MIPS32} ${MIPS64} ${S390X} ${SPARC} ${SPARCV9}
     ${HEXAGON} ${LOONGARCH64})
 set(ALL_ASAN_SUPPORTED_ARCH ${X86} ${X86_64} ${ARM32} ${ARM64} ${RISCV64}
-    ${MIPS32} ${MIPS64} ${PPC64} ${S390X} ${SPARC} ${SPARCV9} ${HEXAGON})
+    ${MIPS32} ${MIPS64} ${PPC64} ${S390X} ${SPARC} ${SPARCV9} ${HEXAGON}
+    ${LOONGARCH64})
 set(ALL_DFSAN_SUPPORTED_ARCH ${X86_64} ${MIPS64} ${ARM64})
 
 if(ANDROID)

compiler-rt/lib/asan/asan_interceptors_vfork.S

@@ -6,6 +6,7 @@
 #include "sanitizer_common/sanitizer_common_interceptors_vfork_aarch64.inc.S"
 #include "sanitizer_common/sanitizer_common_interceptors_vfork_arm.inc.S"
 #include "sanitizer_common/sanitizer_common_interceptors_vfork_i386.inc.S"
+#include "sanitizer_common/sanitizer_common_interceptors_vfork_loongarch64.inc.S"
 #include "sanitizer_common/sanitizer_common_interceptors_vfork_riscv64.inc.S"
 #include "sanitizer_common/sanitizer_common_interceptors_vfork_x86_64.inc.S"
 #endif

compiler-rt/lib/asan/asan_mapping.h

@@ -114,6 +114,13 @@
 // || `[0x0080000000000, 0x008ffffffffff]` || LowShadow  ||
 // || `[0x0000000000000, 0x007ffffffffff]` || LowMem     ||
 //
+// Default Linux/LoongArch64 (47-bit VMA) mapping:
+// || `[0x500000000000, 0x7fffffffffff]` || HighMem    ||
+// || `[0x4a0000000000, 0x4fffffffffff]` || HighShadow ||
+// || `[0x480000000000, 0x49ffffffffff]` || ShadowGap  ||
+// || `[0x400000000000, 0x47ffffffffff]` || LowShadow  ||
+// || `[0x000000000000, 0x3fffffffffff]` || LowMem     ||
+//
 // Shadow mapping on FreeBSD/x86-64 with SHADOW_OFFSET == 0x400000000000:
 // || `[0x500000000000, 0x7fffffffffff]` || HighMem    ||
 // || `[0x4a0000000000, 0x4fffffffffff]` || HighShadow ||
@@ -196,6 +203,8 @@
 #    define ASAN_SHADOW_OFFSET_CONST 0x0000002000000000
 #  elif defined(__sparc__)
 #    define ASAN_SHADOW_OFFSET_CONST 0x0000080000000000
+#  elif SANITIZER_LOONGARCH64
+#    define ASAN_SHADOW_OFFSET_CONST 0x0000400000000000
 #  elif SANITIZER_WINDOWS64
 #    define ASAN_SHADOW_OFFSET_DYNAMIC
 #  else

compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors_vfork_loongarch64.inc.S

@@ -0,0 +1,63 @@
+#if defined(__loongarch_lp64) && defined(__linux__)
+
+#include "sanitizer_common/sanitizer_asm.h"
+
+ASM_HIDDEN(COMMON_INTERCEPTOR_SPILL_AREA)
+ASM_HIDDEN(_ZN14__interception10real_vforkE)
+
+.bss
+.type _ZN14__interception10real_vforkE, @object
+.size _ZN14__interception10real_vforkE, 8
+_ZN14__interception10real_vforkE:
+        .zero     8
+
+.text
+.globl ASM_WRAPPER_NAME(vfork)
+ASM_TYPE_FUNCTION(ASM_WRAPPER_NAME(vfork))
+ASM_WRAPPER_NAME(vfork):
+        // Save ra in the off-stack spill area.
+        // allocate space on stack
+        addi.d    $sp, $sp, -16
+        // store $ra value
+        st.d      $ra, $sp, 8
+        bl        COMMON_INTERCEPTOR_SPILL_AREA
+        // restore previous values from stack
+        ld.d      $ra, $sp, 8
+        // adjust stack
+        addi.d    $sp, $sp, 16
+        // store $ra by $a0
+        st.d      $ra, $a0, 0
+
+        // Call real vfork. This may return twice. User code that runs between the first and the second return
+        // may clobber the stack frame of the interceptor; that's why it does not have a frame.
+        la.local  $a0, _ZN14__interception10real_vforkE
+        ld.d      $a0, $a0, 0
+        jirl      $ra, $a0, 0
+
+        // adjust stack
+        addi.d    $sp, $sp, -16
+        // store $a0 by adjusted stack
+        st.d      $a0, $sp, 8
+        // jump to exit label if $a0 is 0
+        beqz      $a0, .L_exit
+
+        // $a0 != 0 => parent process. Clear stack shadow.
+        // put old $sp to $a0
+        addi.d    $a0, $sp, 16
+        bl        %plt(COMMON_INTERCEPTOR_HANDLE_VFORK)
+
+.L_exit:
+        // Restore $ra
+        bl        COMMON_INTERCEPTOR_SPILL_AREA
+        ld.d      $ra, $a0, 0
+        // load value by stack
+        ld.d      $a0, $sp, 8
+        // adjust stack
+        addi.d    $sp, $sp, 16
+        jr        $ra
+ASM_SIZE(vfork)
+
+.weak vfork
+.set vfork, ASM_WRAPPER_NAME(vfork)
+
+#endif

compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.cpp

@@ -121,7 +121,7 @@ void BufferedStackTrace::UnwindFast(uptr pc, uptr bp, uptr stack_top,
     uhwptr pc1 = caller_frame[2];
 #elif defined(__s390__)
     uhwptr pc1 = frame[14];
-#elif defined(__riscv)
+#elif defined(__loongarch__) || defined(__riscv)
     // frame[-1] contains the return address
     uhwptr pc1 = frame[-1];
 #else
@@ -136,7 +136,7 @@ void BufferedStackTrace::UnwindFast(uptr pc, uptr bp, uptr stack_top,
       trace_buffer[size++] = (uptr) pc1;
     }
     bottom = (uptr)frame;
-#if defined(__riscv)
+#if defined(__loongarch__) || defined(__riscv)
     // frame[-2] contain fp of the previous frame
     uptr new_bp = (uptr)frame[-2];
 #else