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[PATCH] S/390: Run %a0:DI splitters only after reload
- From: Ilya Leoshkevich <iii at linux dot ibm dot com>
- To: gcc-patches at gcc dot gnu dot org, krebbel at linux dot ibm dot com
- Cc: rdapp at linux dot ibm dot com, stli at linux dot ibm dot com, Ilya Leoshkevich <iii at linux dot ibm dot com>
- Date: Fri, 11 Oct 2019 18:35:22 +0200
- Subject: [PATCH] S/390: Run %a0:DI splitters only after reload
Bootstrapped and regtested on s390x-redhat-linux.
gcc/ChangeLog:
2019-10-10 Ilya Leoshkevich <iii@linux.ibm.com>
* config/s390/s390.md: Run %a0:DI splitters only after reload.
gcc/testsuite/ChangeLog:
2019-10-10 Ilya Leoshkevich <iii@linux.ibm.com>
* gcc.target/s390/load-thread-pointer-once.c: New test.
---
gcc/config/s390/s390.md | 13 ++++++++++---
.../gcc.target/s390/load-thread-pointer-once.c | 12 ++++++++++++
2 files changed, 22 insertions(+), 3 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/s390/load-thread-pointer-once.c
diff --git a/gcc/config/s390/s390.md b/gcc/config/s390/s390.md
index 4f7bde6616b..1e6439d5fd6 100644
--- a/gcc/config/s390/s390.md
+++ b/gcc/config/s390/s390.md
@@ -1860,10 +1860,17 @@
*,*,yes")
])
+; Splitters for loading/storing TLS pointers from/to %a0:DI.
+; Do this only during split2, which runs after reload. At the point when split1
+; runs, some of %a0:DI occurrences might be nested inside other rtxes and thus
+; not matched. As a result, only some occurrences will be split, which will
+; prevent CSE. At the point when split2 runs, reload will have ensured that no
+; nested references exist.
+
(define_split
[(set (match_operand:DI 0 "register_operand" "")
(match_operand:DI 1 "register_operand" ""))]
- "TARGET_ZARCH && ACCESS_REG_P (operands[1])"
+ "TARGET_ZARCH && ACCESS_REG_P (operands[1]) && reload_completed"
[(set (match_dup 2) (match_dup 3))
(set (match_dup 0) (ashift:DI (match_dup 0) (const_int 32)))
(set (strict_low_part (match_dup 2)) (match_dup 4))]
@@ -1873,7 +1880,7 @@
(define_split
[(set (match_operand:DI 0 "register_operand" "")
(match_operand:DI 1 "register_operand" ""))]
- "TARGET_ZARCH && ACCESS_REG_P (operands[0])
+ "TARGET_ZARCH && ACCESS_REG_P (operands[0]) && reload_completed
&& dead_or_set_p (insn, operands[1])"
[(set (match_dup 3) (match_dup 2))
(set (match_dup 1) (lshiftrt:DI (match_dup 1) (const_int 32)))
@@ -1884,7 +1891,7 @@
(define_split
[(set (match_operand:DI 0 "register_operand" "")
(match_operand:DI 1 "register_operand" ""))]
- "TARGET_ZARCH && ACCESS_REG_P (operands[0])
+ "TARGET_ZARCH && ACCESS_REG_P (operands[0]) && reload_completed
&& !dead_or_set_p (insn, operands[1])"
[(set (match_dup 3) (match_dup 2))
(set (match_dup 1) (rotate:DI (match_dup 1) (const_int 32)))
diff --git a/gcc/testsuite/gcc.target/s390/load-thread-pointer-once.c b/gcc/testsuite/gcc.target/s390/load-thread-pointer-once.c
new file mode 100644
index 00000000000..21a5bfaa732
--- /dev/null
+++ b/gcc/testsuite/gcc.target/s390/load-thread-pointer-once.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+
+__thread void *foo;
+
+void *bar()
+{
+ return (foo = __builtin_thread_pointer());
+}
+
+/* { dg-final { scan-assembler-times {\n\tear\t} 2 { target { lp64 } } } } */
+/* { dg-final { scan-assembler-times {\n\tear\t} 1 { target { ! lp64 } } } } */
--
2.23.0