Don't assume that stack slots can only be accessed by stack or frame
registers. Also check memory accesses from registers defined by
stack or frame registers.
gcc/
PR target/109780
* config/i386/i386.cc (ix86_set_with_register_source): New.
(ix86_find_all_stack_access): Likewise.
(ix86_find_max_used_stack_alignment): Also check memory accesses
from registers defined by stack or frame registers.
gcc/testsuite/
PR target/109780
* g++.target/i386/pr109780-1.C: New test.
* gcc.target/i386/pr109780-1.c: Likewise.
* gcc.target/i386/pr109780-2.c: Likewise.
---
gcc/config/i386/i386.cc | 145 ++++++++++++++++++---
gcc/testsuite/g++.target/i386/pr109780-1.C | 72 ++++++++++
gcc/testsuite/gcc.target/i386/pr109780-1.c | 14 ++
gcc/testsuite/gcc.target/i386/pr109780-2.c | 21 +++
4 files changed, 233 insertions(+), 19 deletions(-)
create mode 100644 gcc/testsuite/g++.target/i386/pr109780-1.C
create mode 100644 gcc/testsuite/gcc.target/i386/pr109780-1.c
create mode 100644 gcc/testsuite/gcc.target/i386/pr109780-2.c
diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index caca74d6dec..85dd8cb0581 100644
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -8084,6 +8084,72 @@ output_probe_stack_range (rtx reg, rtx end)
return "";
}
+/* Check if PAT is a SET with register source. */
+
+static void
+ix86_set_with_register_source (rtx, const_rtx pat, void *data)
+{
+ if (GET_CODE (pat) != SET)
+ return;
+
+ rtx src = SET_SRC (pat);
+ if (MEM_P (src) || CONST_INT_P (src))
+ return;
+
+ bool *may_use_register = (bool *) data;
+ *may_use_register = true;
+}
+
+/* Find all register access registers. */
+
+static bool
+ix86_find_all_stack_access (HARD_REG_SET &stack_slot_access)
+{
+ bool repeat = false;
+
+ for (int i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ if (GENERAL_REGNO_P (i)
+ && !TEST_HARD_REG_BIT (stack_slot_access, i))
+ for (df_ref def = DF_REG_DEF_CHAIN (i);
+ def != NULL;
+ def = DF_REF_NEXT_REG (def))
+ {
+ if (DF_REF_IS_ARTIFICIAL (def))
+ continue;
+
+ rtx_insn *insn = DF_REF_INSN (def);
+
+ bool may_use_register = false;
+ note_stores (insn, ix86_set_with_register_source,
+ &may_use_register);
+
+ if (!may_use_register)
+ continue;
+
+ df_ref use;
+ FOR_EACH_INSN_USE (use, insn)
+ {
+ rtx reg = DF_REF_REG (use);
+
+ if (!REG_P (reg))
+ continue;
+
+ /* Skip if stack slot access register isn't used. */
+ if (!TEST_HARD_REG_BIT (stack_slot_access,
+ REGNO (reg)))
+ continue;
+
+ /* Add this register to stack_slot_access. */
+ add_to_hard_reg_set (&stack_slot_access, Pmode, i);
+
+ /* Repeat if a register is added to stack_slot_access. */
+ repeat = true;
+ }
+ }
+
+ return repeat;
+}
+
/* Set stack_frame_required to false if stack frame isn't required.
Update STACK_ALIGNMENT to the largest alignment, in bits, of stack
slot used if stack frame is required and CHECK_STACK_SLOT is true. */
@@ -8092,15 +8158,23 @@ static void
ix86_find_max_used_stack_alignment (unsigned int &stack_alignment,
bool check_stack_slot)
{
- HARD_REG_SET set_up_by_prologue, prologue_used;
+ HARD_REG_SET set_up_by_prologue, prologue_used, stack_slot_access;
basic_block bb;
CLEAR_HARD_REG_SET (prologue_used);
CLEAR_HARD_REG_SET (set_up_by_prologue);
+ CLEAR_HARD_REG_SET (stack_slot_access);
add_to_hard_reg_set (&set_up_by_prologue, Pmode, STACK_POINTER_REGNUM);
add_to_hard_reg_set (&set_up_by_prologue, Pmode, ARG_POINTER_REGNUM);
add_to_hard_reg_set (&set_up_by_prologue, Pmode,
HARD_FRAME_POINTER_REGNUM);
+ /* Stack slot can be accessed by stack pointer, frame pointer or
+ registers defined by stack pointer or frame pointer. */
+ add_to_hard_reg_set (&stack_slot_access, Pmode,
+ STACK_POINTER_REGNUM);
+ if (frame_pointer_needed)
+ add_to_hard_reg_set (&stack_slot_access, Pmode,
+ HARD_FRAME_POINTER_REGNUM);
/* The preferred stack alignment is the minimum stack alignment. */
if (stack_alignment > crtl->preferred_stack_boundary)
@@ -8108,32 +8182,65 @@ ix86_find_max_used_stack_alignment (unsigned int
&stack_alignment,
bool require_stack_frame = false;
+ /* Find all register access registers. */
+ while (ix86_find_all_stack_access (stack_slot_access))
+ ;
+
FOR_EACH_BB_FN (bb, cfun)
{
rtx_insn *insn;
FOR_BB_INSNS (bb, insn)
- if (NONDEBUG_INSN_P (insn)
- && requires_stack_frame_p (insn, prologue_used,
- set_up_by_prologue))
+ if (NONDEBUG_INSN_P (insn))
{
- require_stack_frame = true;
+ if (!require_stack_frame)
+ {
+ if (requires_stack_frame_p (insn, prologue_used,
+ set_up_by_prologue))
+ require_stack_frame = true;
+ else
+ /* Skip if stack frame isn't required. */
+ continue;
+ }
- if (check_stack_slot)
+ /* Stop if stack frame is required, but we don't need to
+ check stack slot. */
+ if (!check_stack_slot)
+ break;
+
+ /* Find stack slot access register use. */
+ bool stack_slot_register_p = false;
+ df_ref use;
+ FOR_EACH_INSN_USE (use, insn)
{
- /* Find the maximum stack alignment. */
- subrtx_iterator::array_type array;
- FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
- if (MEM_P (*iter)
- && (reg_mentioned_p (stack_pointer_rtx,
- *iter)
- || reg_mentioned_p (frame_pointer_rtx,
- *iter)))
- {
- unsigned int alignment = MEM_ALIGN (*iter);
- if (alignment > stack_alignment)
- stack_alignment = alignment;
- }
+ rtx reg = DF_REF_REG (use);
+
+ if (!REG_P (reg))
+ continue;
+
+ /* Stop if stack slot access register is used. */
+ if (TEST_HARD_REG_BIT (stack_slot_access,
+ REGNO (reg)))
+ {
+ stack_slot_register_p = true;
+ break;
+ }
}
+
+ /* Skip if stack slot access registers are unused. */
+ if (!stack_slot_register_p)
+ continue;
+
+ /* This insn may reference stack slot. Find the maximum
+ stack slot alignment. */
+ subrtx_iterator::array_type array;
+ FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
+ if (MEM_P (*iter))
+ {
+ unsigned int alignment = MEM_ALIGN (*iter);
+ if (alignment > stack_alignment)
+ stack_alignment = alignment;
+ break;
+ }
}
}
diff --git a/gcc/testsuite/g++.target/i386/pr109780-1.C
b/gcc/testsuite/g++.target/i386/pr109780-1.C
new file mode 100644
index 00000000000..7e3eabdec94
--- /dev/null
+++ b/gcc/testsuite/g++.target/i386/pr109780-1.C
@@ -0,0 +1,72 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target c++17 } */
+/* { dg-options "-O2 -mavx2 -mtune=haswell" } */
+
+template <typename _Tp> struct remove_reference {
+ using type = __remove_reference(_Tp);
+};
+template <typename T> struct MaybeStorageBase {
+ T val;
+ struct Union {
+ ~Union();
+ } mStorage;
+};
+template <typename T> struct MaybeStorage : MaybeStorageBase<T> {
+ char mIsSome;
+};
+template <typename T, typename U = typename remove_reference<T>::type>
+constexpr MaybeStorage<U> Some(T &&);
+template <typename T, typename U> constexpr MaybeStorage<U> Some(T &&aValue) {
+ return {aValue};
+}
+template <class> struct Span {
+ int operator[](long idx) {
+ int *__trans_tmp_4;
+ if (__builtin_expect(idx, 0))
+ *(int *)__null = false;
+ __trans_tmp_4 = storage_.data();
+ return __trans_tmp_4[idx];
+ }
+ struct {
+ int *data() { return data_; }
+ int *data_;
+ } storage_;
+};
+struct Variant {
+ template <typename RefT> Variant(RefT) {}
+};
+long from_i, from___trans_tmp_9;
+namespace js::intl {
+struct DecimalNumber {
+ Variant string_;
+ unsigned long significandStart_;
+ unsigned long significandEnd_;
+ bool zero_ = false;
+ bool negative_;
+ template <typename CharT> DecimalNumber(CharT string) : string_(string) {}
+ template <typename CharT>
+ static MaybeStorage<DecimalNumber> from(Span<const CharT>);
+ void from();
+};
+} // namespace js::intl
+void js::intl::DecimalNumber::from() {
+ Span<const char16_t> __trans_tmp_3;
+ from(__trans_tmp_3);
+}
+template <typename CharT>
+MaybeStorage<js::intl::DecimalNumber>
+js::intl::DecimalNumber::from(Span<const CharT> chars) {
+ DecimalNumber number(chars);
+ if (auto ch = chars[from_i]) {
+ from_i++;
+ number.negative_ = ch == '-';
+ }
+ while (from___trans_tmp_9 && chars[from_i])
+ ;
+ if (chars[from_i])
+ while (chars[from_i - 1])
+ number.zero_ = true;
+ return Some(number);
+}
+
+/* { dg-final { scan-assembler-not "and\[lq\]?\[^\\n\]*-32,\[^\\n\]*sp" } } */
diff --git a/gcc/testsuite/gcc.target/i386/pr109780-1.c
b/gcc/testsuite/gcc.target/i386/pr109780-1.c
new file mode 100644
index 00000000000..6b06947f2a5
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr109780-1.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=skylake" } */
+
+char perm[64];
+
+void
+__attribute__((noipa))
+foo (int n)
+{
+ for (int i = 0; i < n; ++i)
+ perm[i] = i;
+}
+
+/* { dg-final { scan-assembler-not "and\[lq\]?\[^\\n\]*-32,\[^\\n\]*sp" } } */
diff --git a/gcc/testsuite/gcc.target/i386/pr109780-2.c
b/gcc/testsuite/gcc.target/i386/pr109780-2.c
new file mode 100644
index 00000000000..152da06c6ad
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr109780-2.c
@@ -0,0 +1,21 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -march=skylake" } */
+
+#define N 9
+
+void
+f (double x, double y, double *res)
+{
+ y = -y;
+ for (int i = 0; i < N; ++i)
+ {
+ double tmp = y;
+ y = x;
+ x = tmp;
+ res[i] = i;
+ }
+ res[N] = y * y;
+ res[N + 1] = x;
+}
+
+/* { dg-final { scan-assembler-not "and\[lq\]?\[^\\n\]*-32,\[^\\n\]*sp" } } */
--
2.41.0
