convert_memory_address_addr_space_1 has two modes: one in which it
tries to create a self-contained RTL expression (which might fail)
and one in which it can emit new instructions where necessary.
When handling a CONST, the function recurses into the CONST's
operand and then constifies the result. But that's only valid if
the result is still a self-contained expression. If new instructions
have been emitted, the expression will refer to the (non-constant)
results of those instructions.
In the PR, this caused us to emit a nonsensical (const (reg ...))
REG_EQUAL note.
Tested on aarch64-linux-gnu & x86_64-linux-gnu. OK to install?
Richard
gcc/
PR tree-optimization/108603
* explow.cc (convert_memory_address_addr_space_1): Only wrap
the result of a recursive call in a CONST if no instructions
were emitted.
gcc/testsuite/
PR tree-optimization/108603
* gcc.target/aarch64/sve/pr108603.c: New test.
---
gcc/explow.cc | 11 ++++++++---
gcc/testsuite/gcc.target/aarch64/sve/pr108603.c | 8 ++++++++
2 files changed, 16 insertions(+), 3 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/aarch64/sve/pr108603.c
diff --git a/gcc/explow.cc b/gcc/explow.cc
index 83439b32abe..32e9498ee07 100644
--- a/gcc/explow.cc
+++ b/gcc/explow.cc
@@ -349,9 +349,14 @@ convert_memory_address_addr_space_1 (scalar_int_mode
to_mode ATTRIBUTE_UNUSED,
return temp;
case CONST:
- temp = convert_memory_address_addr_space_1 (to_mode, XEXP (x, 0), as,
- true, no_emit);
- return temp ? gen_rtx_CONST (to_mode, temp) : temp;
+ {
+ auto *last = no_emit ? nullptr : get_last_insn ();
+ temp = convert_memory_address_addr_space_1 (to_mode, XEXP (x, 0), as,
+ true, no_emit);
+ if (temp && (no_emit || last == get_last_insn ()))
+ return gen_rtx_CONST (to_mode, temp);
+ return temp;
+ }
case PLUS:
case MULT:
diff --git a/gcc/testsuite/gcc.target/aarch64/sve/pr108603.c
b/gcc/testsuite/gcc.target/aarch64/sve/pr108603.c
new file mode 100644
index 00000000000..a2aea9f0b12
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/sve/pr108603.c
@@ -0,0 +1,8 @@
+/* { dg-options "-O2 -mabi=ilp32 -fdata-sections" } */
+
+int a[128];
+long long *p;
+void f() {
+ for (long i = 0; i < sizeof(long); i++)
+ p[i] = a[i];
+}
--
2.25.1
