[PATCH] Fix as segfaults on invalid SSE5 insns

Jakub Jelinek jakub@redhat.com
Sat Dec 29 19:13:00 GMT 2007


Gas ATM segfaults on invalid operands like:
permpd  %xmm1, %xmm0, src1(%rip), %xmm0
which current GCC trunk generates on sse5-permpX.c.
While GCC should be fixed, gas shouldn't segfault.

process_drex initializes modrm_reg{,mem} to None (== 65535).  All valid
operands set those two to something else, but in case of invalid operands
process_drex calls as_bad, but leaves those fields at 65535.  Later on
these 2 fields are used as indexes into arrays without checking.

I think it is better to just initialize to 0, i.e. something that won't
crash, we already issued diagnostics and 0 will allow us to get further.

Ok to commit?

2007-12-29  Jakub Jelinek  <jakub@redhat.com>

	* config/tc-i386.c (process_drex): Initialize modrm_reg and
	modrm_regmem to 0 instead of None.

--- gas/config/tc-i386.c.jj	2007-12-27 16:05:37.000000000 +0100
+++ gas/config/tc-i386.c	2007-12-29 20:02:23.000000000 +0100
@@ -3927,8 +3927,8 @@ finalize_imm (void)
 static void
 process_drex (void)
-  i.drex.modrm_reg = None;
-  i.drex.modrm_regmem = None;
+  i.drex.modrm_reg = 0;
+  i.drex.modrm_regmem = 0;
   /* SSE5 4 operand instructions must have the destination the same as 
      one of the inputs.  Figure out the destination register and cache


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