From 746dcfdb7a4b983641ff52b58187c33f77e172fe Mon Sep 17 00:00:00 2001
From: Svyatoslav Scherbina <svyatoslav.scherbina@jetbrains.com>
Date: Wed, 31 Jul 2019 11:38:50 +0300
Subject: [PATCH] Enforce frame pointer for code with debug info on iOS and
 macOS

To improve call stack scanning in optimized -Xg0 binaries.
---
 .../backend/konan/llvm/LlvmAttributes.kt      | 24 +++++++++++++++++++
 .../backend/konan/llvm/LlvmDeclarations.kt    |  5 ----
 2 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/LlvmAttributes.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/LlvmAttributes.kt
index cc3338f0a70..34a7d9986f8 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/LlvmAttributes.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/LlvmAttributes.kt
@@ -5,18 +5,25 @@
 
 package org.jetbrains.kotlin.backend.konan.llvm
 
+import llvm.LLVMAddTargetDependentFunctionAttr
 import llvm.LLVMValueRef
 import org.jetbrains.kotlin.backend.konan.Context
 import org.jetbrains.kotlin.ir.declarations.IrConstructor
 import org.jetbrains.kotlin.ir.declarations.IrFunction
 import org.jetbrains.kotlin.ir.types.isNothing
 import org.jetbrains.kotlin.ir.util.isThrowable
+import org.jetbrains.kotlin.konan.target.Family
 
 internal fun addLlvmAttributes(context: Context, irFunction: IrFunction, llvmFunction: LLVMValueRef) {
     if (irFunction.returnType.isNothing()) {
         setFunctionNoReturn(llvmFunction)
     }
 
+    if (shouldEnforceFramePointer(context)) {
+        // Note: this is default for clang on at least on iOS and macOS.
+        enforceFramePointer(llvmFunction)
+    }
+
     if (mustNotInline(context, irFunction)) {
         setFunctionNoInline(llvmFunction)
     }
@@ -32,3 +39,20 @@ private fun mustNotInline(context: Context, irFunction: IrFunction): Boolean {
 
     return false
 }
+
+private fun shouldEnforceFramePointer(context: Context): Boolean {
+    // TODO: do we still need it?
+    if (!context.shouldOptimize()) {
+        return true
+    }
+
+    return when (context.config.target.family) {
+        Family.OSX, Family.IOS -> context.shouldContainLocationDebugInfo()
+        Family.LINUX, Family.MINGW, Family.ANDROID, Family.WASM, Family.ZEPHYR -> false
+    }
+}
+
+private fun enforceFramePointer(llvmFunction: LLVMValueRef) {
+    LLVMAddTargetDependentFunctionAttr(llvmFunction, "no-frame-pointer-elim", "true")
+    LLVMAddTargetDependentFunctionAttr(llvmFunction, "no-frame-pointer-elim-non-leaf", "")
+}
diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/LlvmDeclarations.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/LlvmDeclarations.kt
index bf313381b21..2434c0b01aa 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/LlvmDeclarations.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/LlvmDeclarations.kt
@@ -371,11 +371,6 @@ private class DeclarationsGeneratorVisitor(override val context: Context) :
             function
         }
 
-        // TODO: do we still need it?
-        if (!context.shouldOptimize()) {
-            LLVMAddTargetDependentFunctionAttr(llvmFunction, "no-frame-pointer-elim", "true")
-        }
-
         this.functions[declaration] = FunctionLlvmDeclarations(llvmFunction)
     }
 }