[compiler-rt] [tsan] Calibrate jmp_buf pointer mangling (PR #216558)

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``````````diff
diff --git a/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp b/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp
index e4299020c..2cb34792e 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp
@@ -78,27 +78,27 @@ extern "C" void *__libc_stack_end;
 void *__libc_stack_end = 0;
 #endif
 
-#if SANITIZER_LINUX && !SANITIZER_GO
-# define CALIBRATE_LONGJMP_SP 1
-#else
-# define CALIBRATE_LONGJMP_SP 0
-#endif
+#  if SANITIZER_LINUX && !SANITIZER_GO
+#    define CALIBRATE_LONGJMP_SP 1
+#  else
+#    define CALIBRATE_LONGJMP_SP 0
+#  endif
 
-#if CALIBRATE_LONGJMP_SP
-#include "interception/interception.h"
+#  if CALIBRATE_LONGJMP_SP
+#    include "interception/interception.h"
 // Must be declared outside of other namespaces.
 DECLARE_REAL(int, _setjmp, void *env)
 #endif
 
 namespace __tsan {
 
-#if CALIBRATE_LONGJMP_SP
+#  if CALIBRATE_LONGJMP_SP
 static void InitializeLongjmpSpMangling();
 // libc stores rotl(sp ^ longjmp_xor_key, longjmp_rot) in jmp_buf.
 // Both values are zero when the stack pointer is stored unchanged.
 static uptr longjmp_xor_key;
 static uptr longjmp_rot;
-#endif
+#  endif
 
 // Runtime detected VMA size.
 uptr vmaSize;
@@ -566,36 +566,36 @@ uptr ExtractLongJmpSp(uptr *env) {
   return UnmangleLongJmpSp(mangled_sp);
 }
 
-#if CALIBRATE_LONGJMP_SP
+#    if CALIBRATE_LONGJMP_SP
 // Read the SP immediately after _setjmp returns. This is the value libc saves.
-NOINLINE static void ProbeLongJmpSp(uptr *sp, uptr *mangled_sp) {
+NOINLINE static void ProbeLongJmpSp(uptr* sp, uptr* mangled_sp) {
   jmp_buf env;
   REAL(_setjmp)(env);
   uptr v;
-#if defined(__x86_64__)
-  asm volatile("mov  %%rsp, %0" : "=r" (v));
-#elif defined(__aarch64__)
-  asm volatile("mov  %0, sp" : "=r" (v));
-#elif defined(__loongarch__)
-  asm volatile("move  %0, $sp" : "=r" (v));
-#elif defined(__powerpc64__)
-  asm volatile("mr  %0, 1" : "=r" (v));
-#elif defined(__s390x__)
-  asm volatile("lgr  %0, %%r15" : "=r" (v));
-#elif defined(__mips__)
-  asm volatile("move  %0, $sp" : "=r" (v));
-#elif SANITIZER_RISCV64
-  asm volatile("mv  %0, sp" : "=r" (v));
-#else
-#error "Unknown platform"
-#endif
+#      if defined(__x86_64__)
+  asm volatile("mov  %%rsp, %0" : "=r"(v));
+#      elif defined(__aarch64__)
+  asm volatile("mov  %0, sp" : "=r"(v));
+#      elif defined(__loongarch__)
+  asm volatile("move  %0, $sp" : "=r"(v));
+#      elif defined(__powerpc64__)
+  asm volatile("mr  %0, 1" : "=r"(v));
+#      elif defined(__s390x__)
+  asm volatile("lgr  %0, %%r15" : "=r"(v));
+#      elif defined(__mips__)
+  asm volatile("move  %0, $sp" : "=r"(v));
+#      elif SANITIZER_RISCV64
+  asm volatile("mv  %0, sp" : "=r"(v));
+#      else
+#        error "Unknown platform"
+#      endif
   *sp = v;
-  *mangled_sp = ((uptr *)&env)[LONG_JMP_SP_ENV_SLOT];
+  *mangled_sp = ((uptr*)&env)[LONG_JMP_SP_ENV_SLOT];
 }
 
 // Run the probe in another frame. Consuming its result after the call prevents
 // tail-call elimination.
-NOINLINE static void ProbeLongJmpSpDeep(uptr *sp, uptr *mangled_sp) {
+NOINLINE static void ProbeLongJmpSpDeep(uptr* sp, uptr* mangled_sp) {
   ProbeLongJmpSp(sp, mangled_sp);
   asm volatile("" : : "r"(*sp));
 }
@@ -629,7 +629,7 @@ static void InitializeLongjmpSpMangling() {
     CHECK(0);
   }
 }
-#endif
+#    endif
 
 extern "C" void __tsan_tls_initialization() {}
 

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https://github.com/llvm/llvm-project/pull/216558