[clang] [llvm] [llvm][clang] Allocate a new stack instead of spawning a new thread to get more stack space (PR #133173)

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github-actions[bot] wrote:

<!--LLVM CODE FORMAT COMMENT: {clang-format}-->


:warning: C/C++ code formatter, clang-format found issues in your code. :warning:

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git-clang-format --diff bfe85230e2dc27493b82ffba5a46c8f7449a6e10 bfd36727df42b6bc95468e84a74efbbff968e7aa --extensions cpp,h -- llvm/include/llvm/Support/ProgramStack.h llvm/lib/Support/ProgramStack.cpp llvm/unittests/Support/ProgramStackTest.cpp clang/include/clang/Basic/Stack.h clang/lib/Basic/Stack.cpp clang/lib/Frontend/CompilerInstance.cpp llvm/include/llvm/Support/CrashRecoveryContext.h llvm/lib/Support/CrashRecoveryContext.cpp
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<details>
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View the diff from clang-format here.
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``````````diff
diff --git a/clang/lib/Basic/Stack.cpp b/clang/lib/Basic/Stack.cpp
index 8cbb84943f..aa3862a957 100644
--- a/clang/lib/Basic/Stack.cpp
+++ b/clang/lib/Basic/Stack.cpp
@@ -49,10 +49,12 @@ void clang::runWithSufficientStackSpaceSlow(llvm::function_ref<void()> Diag,
   llvm::CrashRecoveryContext CRC;
   // Preserve the BottomOfStack in case RunSafelyOnNewStack uses split stacks.
   uintptr_t PrevBottom = BottomOfStack;
-  CRC.RunSafelyOnNewStack([&] {
-    noteBottomOfStack(true);
-    Diag();
-    Fn();
-  }, DesiredStackSize);
+  CRC.RunSafelyOnNewStack(
+      [&] {
+        noteBottomOfStack(true);
+        Diag();
+        Fn();
+      },
+      DesiredStackSize);
   BottomOfStack = PrevBottom;
 }
diff --git a/llvm/lib/Support/ProgramStack.cpp b/llvm/lib/Support/ProgramStack.cpp
index 3a48e86062..1ddfc38848 100644
--- a/llvm/lib/Support/ProgramStack.cpp
+++ b/llvm/lib/Support/ProgramStack.cpp
@@ -11,24 +11,24 @@
 #include "llvm/Support/Compiler.h"
 
 #ifdef HAVE_SYS_RESOURCE_H
-# include <sys/resource.h>
+#include <sys/resource.h>
 #endif
 
 #ifdef _MSC_VER
-# include <intrin.h>  // for _AddressOfReturnAddress
+#include <intrin.h> // for _AddressOfReturnAddress
 #endif
 
 // Currently only Apple AArch64 is known to support split stacks in the debugger
 // and other tooling.
 #if defined(__APPLE__) && defined(__aarch64__) &&                              \
     LLVM_HAS_CPP_ATTRIBUTE(gnu::naked) && __has_extension(gnu_asm)
-# define LLVM_HAS_SPLIT_STACKS
-# define LLVM_HAS_SPLIT_STACKS_AARCH64
+#define LLVM_HAS_SPLIT_STACKS
+#define LLVM_HAS_SPLIT_STACKS_AARCH64
 #include <sys/mman.h>
 #endif
 
 #ifndef LLVM_HAS_SPLIT_STACKS
-# include "llvm/Support/thread.h"
+#include "llvm/Support/thread.h"
 #endif
 
 using namespace llvm;
@@ -65,32 +65,28 @@ namespace {
 #ifdef LLVM_HAS_SPLIT_STACKS_AARCH64
 [[gnu::naked]] void runOnNewStackImpl(void *Stack, void (*Fn)(void *),
                                       void *Ctx) {
-  __asm__ volatile(
-      "mov       x16, sp\n\t"
-      "sub       x0, x0, #0x20\n\t"            // subtract space from stack
-      "stp       xzr, x16, [x0, #0x00]\n\t"    // save old sp
-      "stp       x29, x30, [x0, #0x10]\n\t"    // save fp, lr
-      "mov       sp, x0\n\t"                   // switch to new stack
-      "add       x29, x0, #0x10\n\t"           // switch to new frame
-      ".cfi_def_cfa w29, 16\n\t"
-      ".cfi_offset w30, -8\n\t"                // lr
-      ".cfi_offset w29, -16\n\t"               // fp
-
-      "mov       x0, x2\n\t"                   // Ctx is the only argument
-      "blr       x1\n\t"                       // call Fn
-
-      "ldp       x29, x30, [sp, #0x10]\n\t"    // restore fp, lr
-      "ldp       xzr, x16, [sp, #0x00]\n\t"    // load old sp
-      "mov       sp, x16\n\t"
-      "ret"
-  );
+  __asm__ volatile("mov       x16, sp\n\t"
+                   "sub       x0, x0, #0x20\n\t" // subtract space from stack
+                   "stp       xzr, x16, [x0, #0x00]\n\t" // save old sp
+                   "stp       x29, x30, [x0, #0x10]\n\t" // save fp, lr
+                   "mov       sp, x0\n\t"                // switch to new stack
+                   "add       x29, x0, #0x10\n\t"        // switch to new frame
+                   ".cfi_def_cfa w29, 16\n\t"
+                   ".cfi_offset w30, -8\n\t"  // lr
+                   ".cfi_offset w29, -16\n\t" // fp
+
+                   "mov       x0, x2\n\t" // Ctx is the only argument
+                   "blr       x1\n\t"     // call Fn
+
+                   "ldp       x29, x30, [sp, #0x10]\n\t" // restore fp, lr
+                   "ldp       xzr, x16, [sp, #0x00]\n\t" // load old sp
+                   "mov       sp, x16\n\t"
+                   "ret");
 }
 #endif
 
 #ifdef LLVM_HAS_SPLIT_STACKS
-void callback(void *Ctx) {
-  (*reinterpret_cast<function_ref<void()> *>(Ctx))();
-}
+void callback(void *Ctx) { (*reinterpret_cast<function_ref<void()> *>(Ctx))(); }
 #endif
 } // namespace
 

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https://github.com/llvm/llvm-project/pull/133173