Hi! Since richi's create_mem_ref_raw change to avoid creating TMR if base is not ADDR_EXPR we can ICE, if base is NULL and offset some non-zero constant, because (plus:DI (const_int 0) (const_int 16)) is created. The second hunk fixes it by not adding the 0 in (the routine ends with if (!*addr) *addr = const0_rtx; so it is fine not to add it), the third hunk is an alternative fix, because it is fine to create MEM_REF in that case too (both base and offset are constants). Either of the hunks fixes this, but it doesn't hurt to put in both.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? 2011-05-31 Jakub Jelinek <ja...@redhat.com> PR rtl-optimization/49235 * tree-ssa-address.c (gen_addr_rtx): Ignore base if it is const0_rtx. (create_mem_ref_raw): Create MEM_REF even if base is INTEGER_CST. * gcc.dg/pr49235.c: New test. --- gcc/tree-ssa-address.c.jj 2011-05-31 08:03:10.000000000 +0200 +++ gcc/tree-ssa-address.c 2011-05-31 09:34:21.000000000 +0200 @@ -1,5 +1,5 @@ /* Memory address lowering and addressing mode selection. - Copyright (C) 2004, 2006, 2007, 2008, 2009, 2010 + Copyright (C) 2004, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc. This file is part of GCC. @@ -129,7 +129,7 @@ gen_addr_rtx (enum machine_mode address_ *addr = act_elem; } - if (base) + if (base && base != const0_rtx) { if (*addr) *addr = simplify_gen_binary (PLUS, address_mode, base, *addr); @@ -365,7 +365,7 @@ create_mem_ref_raw (tree type, tree alia ??? As IVOPTs does not follow restrictions to where the base pointer may point to create a MEM_REF only if we know that base is valid. */ - if (TREE_CODE (base) == ADDR_EXPR + if ((TREE_CODE (base) == ADDR_EXPR || TREE_CODE (base) == INTEGER_CST) && (!index2 || integer_zerop (index2)) && (!addr->index || integer_zerop (addr->index))) return fold_build2 (MEM_REF, type, base, addr->offset); --- gcc/testsuite/gcc.dg/pr49235.c.jj 2011-05-31 09:42:50.000000000 +0200 +++ gcc/testsuite/gcc.dg/pr49235.c 2011-05-31 09:40:02.000000000 +0200 @@ -0,0 +1,25 @@ +/* PR rtl-optimization/49235 */ +/* { dg-do compile { target { int32plus } } } */ +/* { dg-options "-O -fno-delete-null-pointer-checks -fno-tree-scev-cprop -ftree-vectorize -fno-vect-cost-model -w" } */ + +void +foo (void) +{ + unsigned i; + unsigned *p = 0; + for (i = 0; i < 4; ++i) + *p++ = 0; + for (i = 0; i < 4; ++i) + *p++ = 0; +} + +void +bar (void) +{ + unsigned i; + unsigned *p = (unsigned *) (__UINTPTR_TYPE__) 0x12340000; + for (i = 0; i < 4; ++i) + *p++ = 0; + for (i = 0; i < 4; ++i) + *p++ = 0; +} Jakub