Improves the code generation by getting rid of redundant LAs, as seen
in the following example:
- la %r1,0(%r13)
- lg %r4,0(%r1)
+ lg %r4,0(%r13)
Also allows to proceed with the merge of movdi_64 and movdi_larl.
Currently LRA decides to spill literal pool references back to the
literal pool, because it preliminarily chooses alternatives with
CT_MEMORY constraints without calling
satisfies_memory_constraint_p (). Later on it notices that the
constraint is wrong and fixes it by spilling. The constraint in this
case is "b", and the operand is a literal pool reference. There is
no reason to reject them. The current behavior was introduced,
apparently unintentionally, by
https://gcc.gnu.org/ml/gcc-patches/2010-09/msg00812.html
The patch affects a little bit more than mentioned in the subject,
because it changes s390_loadrelative_operand_p (), which is called not
only for checking the "b" constraint. However, the only caller for
which it should really not accept literal pool references is
s390_check_qrst_address (), so it was changed to explicitly do so.
gcc/ChangeLog:
2018-10-22 Ilya Leoshkevich <iii@linux.ibm.com>
* config/s390/s390.c (s390_loadrelative_operand_p): Accept
literal pool references.
(s390_check_qrst_address): Adapt to the new behavior of
s390_loadrelative_operand_p ().
gcc/testsuite/ChangeLog:
2018-10-22 Ilya Leoshkevich <iii@linux.ibm.com>
* gcc.target/s390/litpool-int.c: New test.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@265371
138bc75d-0d04-0410-961f-
82ee72b054a4
+2018-10-22 Ilya Leoshkevich <iii@linux.ibm.com>
+
+ * config/s390/s390.c (s390_loadrelative_operand_p): Accept
+ literal pool references.
+ (s390_check_qrst_address): Adapt to the new behavior of
+ s390_loadrelative_operand_p ().
+
2018-10-22 H.J. Lu <hongjiu.lu@intel.com>
PR target/72782
Valid addresses are single references or a sum of a reference and a
constant integer. Return these parts in SYMREF and ADDEND. You can
pass NULL in REF and/or ADDEND if you are not interested in these
- values. Literal pool references are *not* considered symbol
- references. */
+ values. */
static bool
s390_loadrelative_operand_p (rtx addr, rtx *symref, HOST_WIDE_INT *addend)
addr = XEXP (addr, 0);
}
- if ((GET_CODE (addr) == SYMBOL_REF && !CONSTANT_POOL_ADDRESS_P (addr))
+ if (GET_CODE (addr) == SYMBOL_REF
|| (GET_CODE (addr) == UNSPEC
&& (XINT (addr, 1) == UNSPEC_GOTENT
|| XINT (addr, 1) == UNSPEC_PLT)))
static int
s390_check_qrst_address (char c, rtx op, bool lit_pool_ok)
{
+ rtx symref;
struct s390_address addr;
bool decomposed = false;
/* This check makes sure that no symbolic address (except literal
pool references) are accepted by the R or T constraints. */
- if (s390_loadrelative_operand_p (op, NULL, NULL))
+ if (s390_loadrelative_operand_p (op, &symref, NULL)
+ && (!lit_pool_ok || !CONSTANT_POOL_ADDRESS_P (symref)))
return 0;
/* Ensure literal pool references are only accepted if LIT_POOL_OK. */
+2018-10-22 Ilya Leoshkevich <iii@linux.ibm.com>
+
+ * gcc.target/s390/litpool-int.c: New test.
+
2018-10-22 H.J. Lu <hongjiu.lu@intel.com>
PR target/72782