Hi,
I did not backport my fix of PR 97456 to GCC 9 and it re-surfaced there
as PR 105071. I have cherry-picked the fix, pasted below, on top of the
gcc 9 branch (the only change is an extra bug reference in the
ChangeLog) and made sure it passes bootstrap and testing on
x86_64-linux. Can I commit the backport to the branch?
I think the old testcase is sufficient and so did not add the new one.
Thanks,
Martin
In PR 97456, IPA-SRA triggers a bug in tree-complex.c where it
converts:
<bb 2>
a$_M_value_21 = COMPLEX_EXPR <ISRA.18_10(D), ISRA.18_10(D)>;
(where ISRA.18 is IPA-SRA created PARM_DECL with DECL_IGNORED_P set,
which is why it only happens with IPA-SRA) into:
<bb 2>
a$_M_value_21 = COMPLEX_EXPR <a$_M_value$real_10(D), a$_M_value$real_10(D)>;
i.e. it replaces two uses of the parameter default-def with two
uninitialized default-defs of a new variable - all in hope to produce
code with better debug info.
This patch fixes it by avoiding the transform when the SSA_NAME to be
replaced is a default definition.
gcc/ChangeLog:
2020-10-19 Martin Jambor <mjam...@suse.cz>
PR tree-optimization/97456
PR middle-end/105071
* tree-complex.c (set_component_ssa_name): Do not replace ignored decl
default definitions with new component vars. Reorder if conditions.
gcc/testsuite/ChangeLog:
2020-10-19 Martin Jambor <mjam...@suse.cz>
PR tree-optimization/97456
* gcc.dg/tree-ssa/pr97456.c: New test.
(cherry picked from commit 619f91eaa8c8a50f1f9d3e7b96ee837037f0e806)
---
gcc/testsuite/gcc.dg/tree-ssa/pr97456.c | 40 +++++++++++++++++++++++++
gcc/tree-complex.c | 3 +-
2 files changed, 42 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr97456.c
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr97456.c
b/gcc/testsuite/gcc.dg/tree-ssa/pr97456.c
new file mode 100644
index 00000000000..5171c9b4577
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr97456.c
@@ -0,0 +1,40 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -fwhole-program" } */
+
+
+float val2 = 1.710780f;
+float val3;
+volatile float vf;
+
+int __attribute__((noipa))
+get_bool (void)
+{
+ return 1;
+}
+
+int __attribute__((noinline))
+wrong (float *pos)
+{
+ _Complex float a;
+
+ __real__ a = *pos;
+ __imag__ a = *pos;
+
+ _Complex float b = 0 + 0i;
+
+ b = b + a;
+
+ if (b == 0.0f)
+ return 1;
+
+ vf = __imag__ b;
+ return 0;
+}
+
+int main(int argc, char **argv) {
+ float val = get_bool () == 1 ? val2 : val3;
+
+ if ((wrong(&val), wrong(&val)))
+ __builtin_abort ();
+ return 0;
+}
diff --git a/gcc/tree-complex.c b/gcc/tree-complex.c
index d4b053d68e1..36a4d6f06d5 100644
--- a/gcc/tree-complex.c
+++ b/gcc/tree-complex.c
@@ -569,7 +569,8 @@ set_component_ssa_name (tree ssa_name, bool imag_p, tree
value)
{
/* Replace an anonymous base value with the variable from cvc_lookup.
This should result in better debug info. */
- if (SSA_NAME_VAR (ssa_name)
+ if (!SSA_NAME_IS_DEFAULT_DEF (value)
+ && SSA_NAME_VAR (ssa_name)
&& (!SSA_NAME_VAR (value) || DECL_IGNORED_P (SSA_NAME_VAR (value)))
&& !DECL_IGNORED_P (SSA_NAME_VAR (ssa_name)))
{
--
2.35.1
