GitLab

Bugzilla Link	20
Created on	Jun 19, 2003 14:28
Resolution	FIXED
Resolved on	Dec 01, 2003 19:09
Version	1.00beta
OS	All
Architecture	All
Attachments	bug.sac

Extended Description

The compiler backend generates wrong code the primitive operation reshape().
Example:
  B = reshape( sv, A)
If the rc of A is 1 (A is the last reference of the array) B can reuse the data
vector of A. For the time being the following code is generated:
  CHECK_REUSE( B, A)
    ALLOC_BEGIN( B, ...)
      PRF_RESHAPE__SHAPE( B, ...)
    ALLOC_END( B, ...)
  INC_RC( B)
  IS_NOT_REUSED( B, A)
    COPY_DATA( B, A)
The problem is about the CHECK_REUSE icm which is defined as follows:
  if (RC(B) == 1)
    ASSIGN( B, A)
  else
    /* allocation of B */
Unfortunately, ASSIGN is not correct here since A and B may have incompatible
descriptors! Instead, the following code should be generated:
  if (RC(B) == 1)
    ASSIGN_DESC( B, A)
    ASSIGN_DATA( B, A)
    PRF_RESHAPE__DIM( B, ...)
    PRF_RESHAPE__SHAPE( B, ...)
  else
    ALLOC_BEGIN( B, ...)
      PRF_RESHAPE__SHAPE( B, ...)
    ALLOC_END( B, ...)
  INC_RC( B)
  IS_NOT_REUSED( B, A)
    COPY_DATA( B, A)
or:
  if (RC(B) == 1)
    ASSIGN_DESC( B, A)
  else
    ALLOC_BEGIN( B, ...)
      PRF_RESHAPE__SHAPE( B, ...)
    ALLOC_END( B, ...)
  INC_RC( B)
  IS_REUSED( B, A)
    PRF_RESHAPE__DIM( B, ...)
    PRF_RESHAPE__SHAPE( B, ...)
    ASSIGN_DATA( B, A)
  ELSE
    COPY_DATA( B, A)
A SAC program for reproducing the bug will be given as attachment.