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Fix[memoryutil]: use integer accesses for floats on ARM32 #1

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Merged
artdeell merged 3 commits into from
Dec 29, 2025
Merged

Fix[memoryutil]: use integer accesses for floats on ARM32 #1

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26c9489
Update MemoryUtil.java
artdeell Dec 29, 2025
4b623a3
Update MemoryUtil.java
artdeell Dec 29, 2025
3ff15ce
Update MemoryUtil.java
artdeell Dec 29, 2025
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24 changes: 20 additions & 4 deletions modules/lwjgl/core/src/main/java/org/lwjgl/system/MemoryUtil.java
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Original file line number Diff line number Diff line change
Expand Up @@ -96,6 +96,9 @@ public final class MemoryUtil {
private static final long PARENT_FLOAT;
private static final long PARENT_DOUBLE;

// Float accesses on ARM require 4-byte (or 8-byte) alignment, so we need to make some special considerations for this arch to avoid exploding Java.
private static final boolean FLOAT_REQUIRES_ALIGNMENT = "arm".equals(System.getProperty("os.arch"));

static {
Library.initialize();

Expand Down Expand Up @@ -1906,8 +1909,15 @@ static void memCopyAligned32(int src, int dst, int bytes) {
public static short memGetShort(long ptr) { return UNSAFE.getShort(null, ptr); }
public static int memGetInt(long ptr) { return UNSAFE.getInt(null, ptr); }
public static long memGetLong(long ptr) { return UNSAFE.getLong(null, ptr); }
public static float memGetFloat(long ptr) { return UNSAFE.getFloat(null, ptr); }
public static double memGetDouble(long ptr) { return UNSAFE.getDouble(null, ptr); }
public static float memGetFloat(long ptr) {
if(!FLOAT_REQUIRES_ALIGNMENT) return UNSAFE.getFloat(null, ptr);
// If an explicitly float access is required, go around and do an unaligned integer access first (which is allowed)
else return Float.intBitsToFloat(UNSAFE.getInt(null, ptr));
}
public static double memGetDouble(long ptr) {
if(!FLOAT_REQUIRES_ALIGNMENT) return UNSAFE.getDouble(null, ptr);
else return Double.longBitsToDouble(UNSAFE.getLong(null, ptr));
}
public static long memGetCLong(long ptr) {
return CLONG_SIZE == 8
? UNSAFE.getLong(null, ptr)
Expand All @@ -1924,8 +1934,14 @@ public static long memGetAddress(long ptr) {
public static void memPutShort(long ptr, short value) { UNSAFE.putShort(null, ptr, value); }
public static void memPutInt(long ptr, int value) { UNSAFE.putInt(null, ptr, value); }
public static void memPutLong(long ptr, long value) { UNSAFE.putLong(null, ptr, value); }
public static void memPutFloat(long ptr, float value) { UNSAFE.putFloat(null, ptr, value); }
public static void memPutDouble(long ptr, double value) { UNSAFE.putDouble(null, ptr, value); }
public static void memPutFloat(long ptr, float value) {
if(!FLOAT_REQUIRES_ALIGNMENT) UNSAFE.putFloat(null, ptr, value);
else UNSAFE.putInt(null, ptr, Float.floatToRawIntBits(value));
}
public static void memPutDouble(long ptr, double value) {
if(!FLOAT_REQUIRES_ALIGNMENT) UNSAFE.putDouble(null, ptr, value);
else UNSAFE.putLong(null, ptr, Double.doubleToRawLongBits(value));
}
public static void memPutCLong(long ptr, long value) {
if (CLONG_SIZE == 8) {
UNSAFE.putLong(null, ptr, value);
Expand Down