restore floating point registers from stack in reverse order

CHANGELOG.md

@@ -12,6 +12,7 @@
 
 * Preserve trampoline argument registers in code-coverage builds.
 * Preserve object-hook super trampolines in optimized Release builds, fixing https://github.com/steipete/InterposeKit/issues/29. Thanks to [@Thomvis](https://github.com/Thomvis).
+* Preserve floating-point arguments when object hooks invoke original methods on arm64. Thanks to [@ishutinvv](https://github.com/ishutinvv).
 
 ## 0.01
 

Sources/SuperBuilder/src/ITKSuperBuilder.m

@@ -213,10 +213,10 @@ asm volatile (
 
 #if PROTECT_FLOATING_POINT_REGISTERS
                   // pop {q0-q7}
-                  "ldp q6, q7, [sp], #32\n"
-                  "ldp q4, q5, [sp], #32\n"
-                  "ldp q2, q3, [sp], #32\n"
                   "ldp q0, q1, [sp], #32\n"
+                  "ldp q2, q3, [sp], #32\n"
+                  "ldp q4, q5, [sp], #32\n"
+                  "ldp q6, q7, [sp], #32\n"
 #endif
 
                   // get new return (adr of the objc_super class)

Tests/InterposeKitTests/ObjectInterposeTests.swift

@@ -134,6 +134,26 @@ final class ObjectInterposeTests: InterposeKitTestCase {
         try hook.revert()
     }
 
+    #if arch(arm64)
+        func test8FloatingPointParameters() throws {
+            let testObj = TestClass()
+            let expected = 87_654_321.0
+            XCTAssertEqual(testObj.combine(1, 2, 3, 4, 5, 6, 7, 8), expected)
+
+            let hook = try testObj.hook(#selector(TestClass.combine)) { (store: TypedHook
+                <@convention(c) (AnyObject, Selector, Double, Double, Double, Double,
+                                 Double, Double, Double, Double) -> Double,
+                @convention(block) (AnyObject, Double, Double, Double, Double,
+                                    Double, Double, Double, Double) -> Double>) in {
+                    store.original($0, store.selector, $1, $2, $3, $4, $5, $6, $7, $8)
+                }
+            }
+
+            XCTAssertEqual(testObj.combine(1, 2, 3, 4, 5, 6, 7, 8), expected)
+            try hook.revert()
+        }
+    #endif
+
     func testObjectCallReturn() throws {
         let testObj = TestClass()
         let str = "foo"

Tests/InterposeKitTests/TestClass.swift

@@ -53,6 +53,15 @@ class TestClass: NSObject {
         var1 + var2 + var3 + var4 + var5 + var6
     }
 
+    #if arch(arm64)
+        // swiftlint:disable:next function_parameter_count
+        @objc dynamic func combine(_ value0: Double, _ value1: Double, _ value2: Double, _ value3: Double,
+                                   _ value4: Double, _ value5: Double, _ value6: Double, _ value7: Double) -> Double {
+            value0 + (value1 * 10) + (value2 * 100) + (value3 * 1_000)
+                + (value4 * 10_000) + (value5 * 100_000) + (value6 * 1_000_000) + (value7 * 10_000_000)
+        }
+    #endif
+
     // This requires _objc_msgSendSuper_stret on x64, returns a large struct
     @objc dynamic func invert3DTransform(_ input: CATransform3D) -> CATransform3D {
         input.inverted