Support cstack=vm/vmx on macOS

apangin · apangin · commit f334c51b7eac · 2025-01-01T00:40:14.000Z
diff --git a/src/profiler.cpp b/src/profiler.cpp
@@ -1168,7 +1168,7 @@ Error Profiler::start(Arguments& args, bool reset) {
         return Error("DWARF unwinding is not supported on this platform");
     } else if (_cstack == CSTACK_LBR && _engine != &perf_events) {
         return Error("Branch stack is supported only with PMU events");
-    } else if (_cstack >= CSTACK_VM && !(VMStructs::hasStackStructs() && OS::isLinux())) {
+    } else if (_cstack >= CSTACK_VM && !VMStructs::hasStackStructs()) {
         return Error("VMStructs stack walking is not supported on this JVM/platform");
     }
 
@@ -1329,7 +1329,7 @@ Error Profiler::check(Arguments& args) {
             return Error("DWARF unwinding is not supported on this platform");
         } else if (args._cstack == CSTACK_LBR && _engine != &perf_events) {
             return Error("Branch stack is supported only with PMU events");
-        } else if (args._cstack >= CSTACK_VM && !(VMStructs::hasStackStructs() && OS::isLinux())) {
+        } else if (args._cstack >= CSTACK_VM && !VMStructs::hasStackStructs()) {
             return Error("VMStructs stack walking is not supported on this JVM/platform");
         }
     }
diff --git a/src/stackWalker.cpp b/src/stackWalker.cpp
@@ -31,6 +31,16 @@ static inline bool sameStack(void* hi, void* lo) {
     return (uintptr_t)hi - (uintptr_t)lo < SAME_STACK_DISTANCE;
 }
 
+// AArch64: on Linux, frame link is stored at the top of the frame,
+// while on macOS, frame link is at the bottom.
+static inline uintptr_t defaultSenderSP(uintptr_t sp, uintptr_t fp) {
+#ifdef __APPLE__
+    return sp + 2 * sizeof(void*);
+#else
+    return fp;
+#endif
+}
+
 static inline void fillFrame(ASGCT_CallFrame& frame, ASGCT_CallFrameType type, const char* name) {
     frame.bci = type;
     frame.method_id = (jmethodID)name;
@@ -176,7 +186,7 @@ int StackWalker::walkDwarf(void* ucontext, const void** callchain, int max_depth
             } else if (f->fp_off != DW_SAME_FP) {
                 // AArch64 default_frame
                 pc = stripPointer(SafeAccess::load((void**)(sp + f->pc_off)));
-                sp = fp;
+                sp = defaultSenderSP(sp, fp);
             } else if (depth <= 1) {
                 pc = (const void*)frame.link();
             } else {
@@ -420,7 +430,7 @@ int StackWalker::walkVM(void* ucontext, ASGCT_CallFrame* frames, int max_depth,
             } else if (f->fp_off != DW_SAME_FP) {
                 // AArch64 default_frame
                 pc = stripPointer(*(void**)(sp + f->pc_off));
-                sp = fp;
+                sp = defaultSenderSP(sp, fp);
             } else if (depth <= 1) {
                 pc = (const void*)frame.link();
             } else {

Original file line number	Diff line number	Diff line change
`@@ -1168,7 +1168,7 @@ Error Profiler::start(Arguments& args, bool reset) {`
`1168`	`1168`	`return Error("DWARF unwinding is not supported on this platform");`
`1169`	`1169`	`} else if (_cstack == CSTACK_LBR && _engine != &perf_events) {`
`1170`	`1170`	`return Error("Branch stack is supported only with PMU events");`
`1171`		`- } else if (_cstack >= CSTACK_VM && !(VMStructs::hasStackStructs() && OS::isLinux())) {`
	`1171`	`+ } else if (_cstack >= CSTACK_VM && !VMStructs::hasStackStructs()) {`
`1172`	`1172`	`return Error("VMStructs stack walking is not supported on this JVM/platform");`
`1173`	`1173`	`}`
`1174`	`1174`
`@@ -1329,7 +1329,7 @@ Error Profiler::check(Arguments& args) {`
`1329`	`1329`	`return Error("DWARF unwinding is not supported on this platform");`
`1330`	`1330`	`} else if (args._cstack == CSTACK_LBR && _engine != &perf_events) {`
`1331`	`1331`	`return Error("Branch stack is supported only with PMU events");`
`1332`		`- } else if (args._cstack >= CSTACK_VM && !(VMStructs::hasStackStructs() && OS::isLinux())) {`
	`1332`	`+ } else if (args._cstack >= CSTACK_VM && !VMStructs::hasStackStructs()) {`
`1333`	`1333`	`return Error("VMStructs stack walking is not supported on this JVM/platform");`
`1334`	`1334`	`}`
`1335`	`1335`	`}`