diff options
Diffstat (limited to 'ipa-fix-bit-CPP-when-combined-with-IPA-bit-CP.patch')
| -rw-r--r-- | ipa-fix-bit-CPP-when-combined-with-IPA-bit-CP.patch | 147 |
1 files changed, 0 insertions, 147 deletions
diff --git a/ipa-fix-bit-CPP-when-combined-with-IPA-bit-CP.patch b/ipa-fix-bit-CPP-when-combined-with-IPA-bit-CP.patch deleted file mode 100644 index cd812623cec3..000000000000 --- a/ipa-fix-bit-CPP-when-combined-with-IPA-bit-CP.patch +++ /dev/null @@ -1,147 +0,0 @@ -From d58f078ce2d53e5dab6b3d0d5f960504268e1894 Mon Sep 17 00:00:00 2001 -From: Martin Liska <mliska@suse.cz> -Date: Wed, 12 Aug 2020 09:21:51 +0200 -Subject: [PATCH] ipa: fix bit CPP when combined with IPA bit CP - -As mentioned in the PR, let's consider the following example: - -int -__attribute__((noinline)) -foo(int arg) -{ - if (arg == 3) - return 1; - if (arg == 4) - return 123; - - __builtin_unreachable (); -} - -during WPA we find all calls of the function -(yes the call with value 5 is UBSAN): - - Node: foo/0: - param [0]: 5 [loc_time: 4, loc_size: 2, prop_time: 0, prop_size: 0] - 3 [loc_time: 3, loc_size: 3, prop_time: 0, prop_size: 0] - ctxs: VARIABLE - Bits: value = 0x5, mask = 0x6 - -in LTRANS we have the following VRP info: - - # RANGE [3, 3] NONZERO 3 - -when we AND masks in get_default_value we end up with 6 & 3 = 2 (0x010). -That means the only second (least significant bit) is unknown and -value (5 = 0x101) & ~mask gives us either 7 (0x111) or 5 (0x101). - -That's why if (arg_2(D) == 3) gets optimized to false. - -gcc/ChangeLog: - - PR ipa/96482 - * ipa-cp.c (ipcp_bits_lattice::meet_with_1): Drop value bits - for bits that are unknown. - (ipcp_bits_lattice::set_to_constant): Likewise. - * tree-ssa-ccp.c (get_default_value): Add sanity check that - IPA CP bit info has all bits set to zero in bits that - are unknown. - -gcc/testsuite/ChangeLog: - - PR ipa/96482 - * gcc.dg/ipa/pr96482.c: New test. ---- - gcc/ipa-cp.c | 3 +- - gcc/testsuite/gcc.dg/ipa/pr96482.c | 44 ++++++++++++++++++++++++++++++ - gcc/tree-ssa-ccp.c | 3 ++ - 3 files changed, 49 insertions(+), 1 deletion(-) - create mode 100644 gcc/testsuite/gcc.dg/ipa/pr96482.c - -diff --git a/gcc/ipa-cp.c b/gcc/ipa-cp.c -index 945a69977f3..2b21280d919 100644 ---- a/gcc/ipa-cp.c -+++ b/gcc/ipa-cp.c -@@ -1011,7 +1011,7 @@ ipcp_bits_lattice::set_to_constant (widest_int value, widest_int mask) - { - gcc_assert (top_p ()); - m_lattice_val = IPA_BITS_CONSTANT; -- m_value = value; -+ m_value = wi::bit_and (wi::bit_not (mask), value); - m_mask = mask; - return true; - } -@@ -1048,6 +1048,7 @@ ipcp_bits_lattice::meet_with_1 (widest_int value, widest_int mask, - - widest_int old_mask = m_mask; - m_mask = (m_mask | mask) | (m_value ^ value); -+ m_value &= value; - - if (wi::sext (m_mask, precision) == -1) - return set_to_bottom (); -diff --git a/gcc/testsuite/gcc.dg/ipa/pr96482.c b/gcc/testsuite/gcc.dg/ipa/pr96482.c -new file mode 100644 -index 00000000000..68ead798d28 ---- /dev/null -+++ b/gcc/testsuite/gcc.dg/ipa/pr96482.c -@@ -0,0 +1,44 @@ -+/* PR ipa/96482 */ -+/* { dg-do run } */ -+/* { dg-options "-O2 -flto" } */ -+/* { dg-require-effective-target lto } */ -+ -+int -+__attribute__((noinline)) -+foo(int arg) -+{ -+ if (arg == 3) -+ return 1; -+ if (arg == 4) -+ return 123; -+ -+ __builtin_unreachable (); -+} -+ -+int -+__attribute__((noinline)) -+baz(int x) -+{ -+ if (x != 0) -+ return foo(3); /* called */ -+ -+ return 1; -+} -+ -+int -+__attribute__((noinline)) -+bar(int x) -+{ -+ if (x == 0) -+ return foo(5); /* not executed */ -+ -+ return 1; -+} -+ -+int main(int argc, char **argv) -+{ -+ if (bar(argc) != baz(argc)) -+ __builtin_abort (); -+ -+ return 0; -+} -diff --git a/gcc/tree-ssa-ccp.c b/gcc/tree-ssa-ccp.c -index 7e3921869b8..65dffe06530 100644 ---- a/gcc/tree-ssa-ccp.c -+++ b/gcc/tree-ssa-ccp.c -@@ -306,6 +306,9 @@ get_default_value (tree var) - { - val.lattice_val = CONSTANT; - val.value = value; -+ widest_int ipa_value = wi::to_widest (value); -+ /* Unknown bits from IPA CP must be equal to zero. */ -+ gcc_assert (wi::bit_and (ipa_value, mask) == 0); - val.mask = mask; - if (nonzero_bits != -1) - val.mask &= extend_mask (nonzero_bits, --- -2.28.0 - |