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Fix #3108: conversion opcodes must update runtime type tag #5009

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Merged
shai-almog merged 1 commit into from
May 23, 2026
+89 −35
Merged

Fix #3108: conversion opcodes must update runtime type tag #5009

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27 changes: 15 additions & 12 deletions vm/ByteCodeTranslator/src/cn1_globals.h
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Original file line number Diff line number Diff line change
Expand Up @@ -350,29 +350,32 @@ typedef struct clazz* JAVA_CLASS;
SP[-1].data.l = SP[-1].data.l ^ (*SP).data.l; \
}

#define BC_I2L() SP[-1].data.l = SP[-1].data.i
// Conversion macros must rewrite the runtime type tag too. BC_DUP2_X1 /
// BC_DUP2_X2 / BC_DUP_X2 dispatch via IS_DOUBLE_WORD on the tag, so a stale
// tag corrupts the stack on chained assignments (issue #3108).
#define BC_I2L() do { SP[-1].data.l = SP[-1].data.i; SP[-1].type = CN1_TYPE_LONG; } while(0)

#define BC_L2I() SP[-1].data.i = (JAVA_INT)SP[-1].data.l
#define BC_L2I() do { SP[-1].data.i = (JAVA_INT)SP[-1].data.l; SP[-1].type = CN1_TYPE_INT; } while(0)

#define BC_L2F() SP[-1].data.f = (JAVA_FLOAT)SP[-1].data.l
#define BC_L2F() do { SP[-1].data.f = (JAVA_FLOAT)SP[-1].data.l; SP[-1].type = CN1_TYPE_FLOAT; } while(0)

#define BC_L2D() SP[-1].data.d = (JAVA_DOUBLE)SP[-1].data.l
#define BC_L2D() do { SP[-1].data.d = (JAVA_DOUBLE)SP[-1].data.l; SP[-1].type = CN1_TYPE_DOUBLE; } while(0)

#define BC_I2F() SP[-1].data.f = (JAVA_FLOAT)SP[-1].data.i
#define BC_I2F() do { SP[-1].data.f = (JAVA_FLOAT)SP[-1].data.i; SP[-1].type = CN1_TYPE_FLOAT; } while(0)

#define BC_F2I() SP[-1].data.i = (JAVA_INT)SP[-1].data.f
#define BC_F2I() do { SP[-1].data.i = (JAVA_INT)SP[-1].data.f; SP[-1].type = CN1_TYPE_INT; } while(0)

#define BC_F2L() SP[-1].data.l = (JAVA_LONG)SP[-1].data.f
#define BC_F2L() do { SP[-1].data.l = (JAVA_LONG)SP[-1].data.f; SP[-1].type = CN1_TYPE_LONG; } while(0)

#define BC_F2D() SP[-1].data.d = SP[-1].data.f
#define BC_F2D() do { SP[-1].data.d = SP[-1].data.f; SP[-1].type = CN1_TYPE_DOUBLE; } while(0)

#define BC_D2I() SP[-1].data.i = (JAVA_INT)SP[-1].data.d
#define BC_D2I() do { SP[-1].data.i = (JAVA_INT)SP[-1].data.d; SP[-1].type = CN1_TYPE_INT; } while(0)

#define BC_D2L() SP[-1].data.l = (JAVA_LONG)SP[-1].data.d
#define BC_D2L() do { SP[-1].data.l = (JAVA_LONG)SP[-1].data.d; SP[-1].type = CN1_TYPE_LONG; } while(0)

#define BC_I2D() SP[-1].data.d = SP[-1].data.i
#define BC_I2D() do { SP[-1].data.d = SP[-1].data.i; SP[-1].type = CN1_TYPE_DOUBLE; } while(0)

#define BC_D2F() SP[-1].data.f = (JAVA_FLOAT)SP[-1].data.d
#define BC_D2F() do { SP[-1].data.f = (JAVA_FLOAT)SP[-1].data.d; SP[-1].type = CN1_TYPE_FLOAT; } while(0)

#ifdef CN1_INCLUDE_NPE_CHECKS
#define BC_ARRAYLENGTH() { \
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51 changes: 28 additions & 23 deletions vm/ByteCodeTranslator/src/com/codename1/tools/translator/bytecodes/BasicInstruction.java
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Expand Up @@ -530,52 +530,57 @@ public void appendInstruction(StringBuilder b, List<Instruction> instructions) {
b.append(" SP--; SP[-1].data.l = SP[-1].data.l ^ (*SP).data.l; /* LXOR */\n") ;
break;

// The conversion opcodes below must also rewrite SP[-1].type to
// match the new category. BC_DUP2_X1 / BC_DUP2_X2 / BC_DUP_X2
// dispatch via the runtime tag (IS_DOUBLE_WORD), so a stale tag
// (e.g. INT left over after I2D) sends the dup macro down the
// cat-1 branch and corrupts the stack. See issue #3108.
case Opcodes.I2L:
b.append(" SP[-1].data.l = SP[-1].data.i; /* I2L */\n");
b.append(" SP[-1].data.l = SP[-1].data.i; SP[-1].type = CN1_TYPE_LONG; /* I2L */\n");
break;

case Opcodes.I2F:
b.append(" SP[-1].data.f = (JAVA_FLOAT)SP[-1].data.i; /* I2F */\n");
b.append(" SP[-1].data.f = (JAVA_FLOAT)SP[-1].data.i; SP[-1].type = CN1_TYPE_FLOAT; /* I2F */\n");
break;

case Opcodes.I2D:
b.append(" SP[-1].data.d = SP[-1].data.i; /* I2D */;\n");
b.append(" SP[-1].data.d = SP[-1].data.i; SP[-1].type = CN1_TYPE_DOUBLE; /* I2D */;\n");
break;

case Opcodes.L2I:
b.append(" SP[-1].data.i = (JAVA_INT)SP[-1].data.l; /* L2I */\n");
b.append(" SP[-1].data.i = (JAVA_INT)SP[-1].data.l; SP[-1].type = CN1_TYPE_INT; /* L2I */\n");
break;

case Opcodes.L2F:
b.append(" SP[-1].data.f = (JAVA_FLOAT)SP[-1].data.l; /* L2F */\n");
b.append(" SP[-1].data.f = (JAVA_FLOAT)SP[-1].data.l; SP[-1].type = CN1_TYPE_FLOAT; /* L2F */\n");
break;

case Opcodes.L2D:
b.append(" SP[-1].data.d = (JAVA_DOUBLE)SP[-1].data.l; /* L2D */\n");
b.append(" SP[-1].data.d = (JAVA_DOUBLE)SP[-1].data.l; SP[-1].type = CN1_TYPE_DOUBLE; /* L2D */\n");
break;

case Opcodes.F2I:
b.append(" SP[-1].data.i = (JAVA_INT)SP[-1].data.f; /* F2I */\n");
b.append(" SP[-1].data.i = (JAVA_INT)SP[-1].data.f; SP[-1].type = CN1_TYPE_INT; /* F2I */\n");
break;

case Opcodes.F2L:
b.append(" SP[-1].data.l = (JAVA_LONG)SP[-1].data.f; /* F2L */\n");
b.append(" SP[-1].data.l = (JAVA_LONG)SP[-1].data.f; SP[-1].type = CN1_TYPE_LONG; /* F2L */\n");
break;

case Opcodes.F2D:
b.append(" SP[-1].data.d = SP[-1].data.f; /* F2D */\n");
b.append(" SP[-1].data.d = SP[-1].data.f; SP[-1].type = CN1_TYPE_DOUBLE; /* F2D */\n");
break;

case Opcodes.D2I:
b.append(" SP[-1].data.i = (JAVA_INT)SP[-1].data.d; /* D2I */\n");
b.append(" SP[-1].data.i = (JAVA_INT)SP[-1].data.d; SP[-1].type = CN1_TYPE_INT; /* D2I */\n");
break;

case Opcodes.D2L:
b.append(" SP[-1].data.l = (JAVA_LONG)SP[-1].data.d; /* D2L */\n");
b.append(" SP[-1].data.l = (JAVA_LONG)SP[-1].data.d; SP[-1].type = CN1_TYPE_LONG; /* D2L */\n");
break;

case Opcodes.D2F:
b.append(" SP[-1].data.f = (JAVA_FLOAT)SP[-1].data.d; /* D2F */\n");
b.append(" SP[-1].data.f = (JAVA_FLOAT)SP[-1].data.d; SP[-1].type = CN1_TYPE_FLOAT; /* D2F */\n");
break;

case Opcodes.I2B:
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46 changes: 46 additions & 0 deletions ...ests/src/test/java/com/codename1/tools/translator/BytecodeInstructionIntegrationTest.java
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Original file line number Diff line number Diff line change
Expand Up @@ -1216,6 +1216,52 @@ void putfieldUnfoldedPathUsesPeekNotPop() {
"Object PUTFIELD must not rely on C argument evaluation order:\n" + objC);
}

/**
* Regression test for issue #3108 (second cause).
*
* The widening / narrowing conversion opcodes (I2D, I2L, F2D, F2L, L2D and
* their inverses) used to write the new value into SP[-1].data but leave
* the runtime type tag untouched. BC_DUP2_X1 / BC_DUP2_X2 / BC_DUP_X2
* dispatch via IS_DOUBLE_WORD(...) on that tag, so e.g. PUSH_INT (tag=INT)
* followed by I2D (data updated, tag still INT) followed by DUP2_X1 sent
* the dup through the cat-1 branch and shifted SP by +2 instead of +1.
* The chained assignment "a.x = b.x = (double) someInt" then read garbage
* for the second putfield's operands and crashed with NPE on iOS.
*
* Each cat-changing conversion must rewrite SP[-1].type to the new
* CN1_TYPE_*. Pure-arithmetic conversions (I2B/I2C/I2S, I2F/F2I) are not
* involved in dup-dispatch but are checked for symmetry.
*/
@Test
void conversionOpcodesUpdateRuntimeTypeTag() {
Object[][] cases = {
{Opcodes.I2L, "I2L", "CN1_TYPE_LONG"},
{Opcodes.I2D, "I2D", "CN1_TYPE_DOUBLE"},
{Opcodes.I2F, "I2F", "CN1_TYPE_FLOAT"},
{Opcodes.L2I, "L2I", "CN1_TYPE_INT"},
{Opcodes.L2F, "L2F", "CN1_TYPE_FLOAT"},
{Opcodes.L2D, "L2D", "CN1_TYPE_DOUBLE"},
{Opcodes.F2I, "F2I", "CN1_TYPE_INT"},
{Opcodes.F2L, "F2L", "CN1_TYPE_LONG"},
{Opcodes.F2D, "F2D", "CN1_TYPE_DOUBLE"},
{Opcodes.D2I, "D2I", "CN1_TYPE_INT"},
{Opcodes.D2L, "D2L", "CN1_TYPE_LONG"},
{Opcodes.D2F, "D2F", "CN1_TYPE_FLOAT"},
};
for (Object[] c : cases) {
int opcode = (Integer) c[0];
String name = (String) c[1];
String expectedTypeTag = (String) c[2];
BasicInstruction instr = new BasicInstruction(opcode, 0);
StringBuilder out = new StringBuilder();
instr.appendInstruction(out, new ArrayList<Instruction>());
String emitted = out.toString();
assertTrue(emitted.contains("SP[-1].type = " + expectedTypeTag),
name + " must rewrite SP[-1].type to " + expectedTypeTag
+ " so BC_DUP2_X1 / BC_DUP2_X2 / BC_DUP_X2 dispatch correctly. Emitted:\n" + emitted);
}
}

@Test
void testArithmeticExpressionCoverage() {
// Use tryReduce to construct an ArithmeticExpression since constructor is private
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