diff options
Diffstat (limited to 'src/asm/scala/tools/asm/Frame.java')
-rw-r--r-- | src/asm/scala/tools/asm/Frame.java | 23 |
1 files changed, 16 insertions, 7 deletions
diff --git a/src/asm/scala/tools/asm/Frame.java b/src/asm/scala/tools/asm/Frame.java index bcc3e8450b..85ad3269ab 100644 --- a/src/asm/scala/tools/asm/Frame.java +++ b/src/asm/scala/tools/asm/Frame.java @@ -70,8 +70,8 @@ final class Frame { * stack types. VALUE depends on KIND. For LOCAL types, it is an index in * the input local variable types. For STACK types, it is a position * relatively to the top of input frame stack. For BASE types, it is either - * one of the constants defined in FrameVisitor, or for OBJECT and - * UNINITIALIZED types, a tag and an index in the type table. + * one of the constants defined below, or for OBJECT and UNINITIALIZED + * types, a tag and an index in the type table. * * Output frames can contain types of any kind and with a positive or * negative dimension (and even unassigned types, represented by 0 - which @@ -1417,6 +1417,7 @@ final class Frame { // if t is the NULL type, merge(u,t)=u, so there is no change return false; } else if ((t & (DIM | BASE_KIND)) == (u & (DIM | BASE_KIND))) { + // if t and u have the same dimension and same base kind if ((u & BASE_KIND) == OBJECT) { // if t is also a reference type, and if u and t have the // same dimension merge(u,t) = dim(t) | common parent of the @@ -1425,13 +1426,21 @@ final class Frame { | cw.getMergedType(t & BASE_VALUE, u & BASE_VALUE); } else { // if u and t are array types, but not with the same element - // type, merge(u,t)=java/lang/Object - v = OBJECT | cw.addType("java/lang/Object"); + // type, merge(u,t) = dim(u) - 1 | java/lang/Object + int vdim = ELEMENT_OF + (u & DIM); + v = vdim | OBJECT | cw.addType("java/lang/Object"); } } else if ((t & BASE_KIND) == OBJECT || (t & DIM) != 0) { - // if t is any other reference or array type, - // merge(u,t)=java/lang/Object - v = OBJECT | cw.addType("java/lang/Object"); + // if t is any other reference or array type, the merged type + // is min(udim, tdim) | java/lang/Object, where udim is the + // array dimension of u, minus 1 if u is an array type with a + // primitive element type (and similarly for tdim). + int tdim = (((t & DIM) == 0 || (t & BASE_KIND) == OBJECT) ? 0 + : ELEMENT_OF) + (t & DIM); + int udim = (((u & DIM) == 0 || (u & BASE_KIND) == OBJECT) ? 0 + : ELEMENT_OF) + (u & DIM); + v = Math.min(tdim, udim) | OBJECT + | cw.addType("java/lang/Object"); } else { // if t is any other type, merge(u,t)=TOP v = TOP; |