[PATCH] Fix for PR optimization/13375: ICE in gcse.c

[Richard Earnshaw <rearnsha at arm dot com>]

In gcse.c we have a routine which will look to see if a value being copied 
can be used in its original form.  If it can, then we can eliminate the 
copy and just use the computed value.

When generating Thumb code on ARM this optimization can abort because the 
computed form is a sub-set of a load-multiple multiple operation.  The 
code that enforces the restriction that the computing expression be a 
single-set seems bogus to me, and since we can't easily extract the 
computing expression it seems safer to just disable the optimization in 
this case.  There's certainly no need to abort.

Tested on arm-elf for both arm and Thumb code generation.

R.

2004-01-15  Richard Earnshaw  <rearnsha@arm.com>

	PR optimization/13375
	* gcse.c (handle_avail_expr): Just return if the source is not a
	single set.

Attachment: gcse-par.patch
Description: gcse-par.patch