From 26b6d0b06d4d0f82a2e60299df149ebeb955e851 Mon Sep 17 00:00:00 2001
From: Ayke van Laethem <aykevanlaethem@gmail.com>
Date: Tue, 20 Dec 2022 17:13:33 +0100
Subject: [PATCH] runtime: arm actually has 8-byte alignment

Specification:
https://developer.arm.com/documentation/dui0472/k/C-and-C---Implementation-Details/Basic-data-types-in-ARM-C-and-C--
There are multiple types that have an 8-byte alignment (long long,
double) so we need to use the same maximum alignment in TinyGo.

Fixing this is necessary for the precise GC.
---
 src/runtime/arch_arm.go     | 4 ++--
 src/runtime/arch_cortexm.go | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/runtime/arch_arm.go b/src/runtime/arch_arm.go
index 16d3649b..1868b7eb 100644
--- a/src/runtime/arch_arm.go
+++ b/src/runtime/arch_arm.go
@@ -9,9 +9,9 @@ const TargetBits = 32
 
 const deferExtraRegs = 0
 
-// Align on word boundary.
+// Align on the maximum alignment for this platform (double).
 func align(ptr uintptr) uintptr {
-	return (ptr + 3) &^ 3
+	return (ptr + 7) &^ 7
 }
 
 func getCurrentStackPointer() uintptr {
diff --git a/src/runtime/arch_cortexm.go b/src/runtime/arch_cortexm.go
index 613dfd5f..45134405 100644
--- a/src/runtime/arch_cortexm.go
+++ b/src/runtime/arch_cortexm.go
@@ -15,7 +15,7 @@ const deferExtraRegs = 0
 
 // Align on word boundary.
 func align(ptr uintptr) uintptr {
-	return (ptr + 3) &^ 3
+	return (ptr + 7) &^ 7
 }
 
 func getCurrentStackPointer() uintptr {