[gcc r12-8871] IRA: Make sure array is big enough

[gcc r12-8871] IRA: Make sure array is big enough

[Torbjorn Svensson]

https://gcc.gnu.org/g:72717ec3ab66ba04e16ea84bd092f987a415672e

commit r12-8871-g72717ec3ab66ba04e16ea84bd092f987a415672e
Author: Torbjörn SVENSSON <torbjorn.svensson@foss.st.com>
Date:   Tue Oct 25 11:45:40 2022 +0200

    IRA: Make sure array is big enough
    
    In commit 081c96621da, the call to resize_reg_info() was moved before
    the call to remove_scratches() and the latter one can increase the
    number of regs and that would cause an out of bounds usage on the
    reg_renumber global array.
    
    Without this patch, the following testcase randomly fails with:
    during RTL pass: ira
    In file included from /src/gcc/testsuite/gcc.dg/compat/struct-by-value-5b_y.c:13:
    /src/gcc/testsuite/gcc.dg/compat/struct-by-value-5b_y.c: In function 'checkgSf13':
    /src/gcc/testsuite/gcc.dg/compat/fp-struct-test-by-value-y.h:28:1: internal compiler error: Segmentation fault
    /src/gcc/testsuite/gcc.dg/compat/struct-by-value-5b_y.c:22:1: note: in expansion of macro 'TEST'
    
    gcc/ChangeLog:
    
            * ira.cc: Resize array after reg number increased.
    
    Co-Authored-By: Yvan ROUX <yvan.roux@foss.st.com>
    Signed-off-by: Torbjörn SVENSSON <torbjorn.svensson@foss.st.com>
    
    (cherry picked from commit 4e1d704243a4f3c4ded47cd0d02427bb7efef069)

Diff:
---
 gcc/ira.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/gcc/ira.cc b/gcc/ira.cc
index e3b3c549120..a287026a275 100644
--- a/gcc/ira.cc
+++ b/gcc/ira.cc
@@ -5718,6 +5718,7 @@ ira (FILE *f)
     regstat_free_ri ();
     regstat_init_n_sets_and_refs ();
     regstat_compute_ri ();
+    resize_reg_info ();
   };
 
   int max_regno_before_rm = max_reg_num ();