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[PATCH][AArch64] Fix PR79041
- From: Wilco Dijkstra <Wilco dot Dijkstra at arm dot com>
- To: GCC Patches <gcc-patches at gcc dot gnu dot org>, James Greenhalgh <James dot Greenhalgh at arm dot com>
- Cc: nd <nd at arm dot com>, Yvan Roux <yvan dot roux at linaro dot org>
- Date: Tue, 27 Jun 2017 14:49:38 +0000
- Subject: [PATCH][AArch64] Fix PR79041
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As described in PR79041, -mcmodel=large -mpc-relative-literal-loads
may be used to avoid generating ADRP/ADD or ADRP/LDR. However both
trunk and GCC7 may still emit ADRP for some constant pool literals.
Fix this by adding a aarch64_pcrelative_literal_loads check.
OK for trunk/GCC7 backport?
ChangeLog:
2017-06-27 Wilco Dijkstra <wdijkstr@arm.com>
PR target/79041
* config/aarch64/aarch64.c (aarch64_classify_symbol):
Avoid SYMBOL_SMALL_ABSOLUTE .
* testsuite/gcc.target/aarch64/pr79041-2.c: New test.
--
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 060cd8476d2954119daac495ecb059c9be73edbe..329d244e9cf16dbdf849e5dd02b3999caf0cd5a7 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -10042,7 +10042,7 @@ aarch64_classify_symbol (rtx x, rtx offset)
/* This is alright even in PIC code as the constant
pool reference is always PC relative and within
the same translation unit. */
- if (CONSTANT_POOL_ADDRESS_P (x))
+ if (CONSTANT_POOL_ADDRESS_P (x) && !aarch64_pcrelative_literal_loads)
return SYMBOL_SMALL_ABSOLUTE;
else
return SYMBOL_FORCE_TO_MEM;
diff --git a/gcc/testsuite/gcc.target/aarch64/pr79041-2.c b/gcc/testsuite/gcc.target/aarch64/pr79041-2.c
new file mode 100644
index 0000000000000000000000000000000000000000..e7899725bad2b770f8488a07f99792113275bdf2
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/pr79041-2.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mcmodel=large -mpc-relative-literal-loads" } */
+
+__int128
+t (void)
+{
+ return (__int128)1 << 80;
+}
+
+/* { dg-final { scan-assembler "adr" } } */