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toolchain/gcc: revert a faulty upstream commit that caused miscompiled code

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This broke at least the OKLI loader, but possibly other things as well

Signed-off-by: Felix Fietkau <nbd@nbd.name>
This commit is contained in:
Felix Fietkau 2021-11-16 10:47:43 +01:00
parent 0e561a2aea
commit 0c249ab076
1 changed files with 160 additions and 0 deletions
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toolchain/gcc/patches/11.2.0/001-Revert-Cleanup-range-of-address-calculations.patch Normal file
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@ -0,0 +1,160 @@
From: Felix Fietkau <nbd@nbd.name>
Date: Tue, 16 Nov 2021 10:39:51 +0100
Subject: [PATCH] Revert "Cleanup range of address calculations."
This reverts commit 47923622c663ffad8b14aa93706183290d4f6791.
This commit is causing issues with offset of struct members.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103255
---
delete mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr78655.c
--- a/gcc/gimple-range.cc
+++ b/gcc/gimple-range.cc
@@ -431,9 +431,8 @@ gimple_ranger::range_of_range_op (irange
m_cache.register_dependency (lhs, op2);
}
- if (gimple_code (s) == GIMPLE_ASSIGN
- && gimple_assign_rhs_code (s) == ADDR_EXPR)
- return range_of_address (r, s);
+ if (range_of_non_trivial_assignment (r, s))
+ return true;
if (range_of_expr (range1, op1, s))
{
@@ -447,84 +446,48 @@ gimple_ranger::range_of_range_op (irange
return true;
}
-// Calculate the range of an assignment containing an ADDR_EXPR.
+// Calculate the range of a non-trivial assignment. That is, is one
+// inolving arithmetic on an SSA name (for example, an ADDR_EXPR).
// Return the range in R.
-// If a range cannot be calculated, set it to VARYING and return true.
+//
+// If a range cannot be calculated, return false.
bool
-gimple_ranger::range_of_address (irange &r, gimple *stmt)
+gimple_ranger::range_of_non_trivial_assignment (irange &r, gimple *stmt)
{
- gcc_checking_assert (gimple_code (stmt) == GIMPLE_ASSIGN);
- gcc_checking_assert (gimple_assign_rhs_code (stmt) == ADDR_EXPR);
+ if (gimple_code (stmt) != GIMPLE_ASSIGN)
+ return false;
- bool strict_overflow_p;
- tree expr = gimple_assign_rhs1 (stmt);
- poly_int64 bitsize, bitpos;
- tree offset;
- machine_mode mode;
- int unsignedp, reversep, volatilep;
- tree base = get_inner_reference (TREE_OPERAND (expr, 0), &bitsize,
- &bitpos, &offset, &mode, &unsignedp,
- &reversep, &volatilep);
-
-
- if (base != NULL_TREE
- && TREE_CODE (base) == MEM_REF
- && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
+ tree base = gimple_range_base_of_assignment (stmt);
+ if (base)
{
- tree ssa = TREE_OPERAND (base, 0);
- gcc_checking_assert (irange::supports_type_p (TREE_TYPE (ssa)));
- range_of_expr (r, ssa, stmt);
- range_cast (r, TREE_TYPE (gimple_assign_rhs1 (stmt)));
-
- poly_offset_int off = 0;
- bool off_cst = false;
- if (offset == NULL_TREE || TREE_CODE (offset) == INTEGER_CST)
+ if (TREE_CODE (base) == MEM_REF)
{
- off = mem_ref_offset (base);
- if (offset)
- off += poly_offset_int::from (wi::to_poly_wide (offset),
- SIGNED);
- off <<= LOG2_BITS_PER_UNIT;
- off += bitpos;
- off_cst = true;
+ if (TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
+ {
+ int_range_max range1;
+ tree ssa = TREE_OPERAND (base, 0);
+ if (range_of_expr (range1, ssa, stmt))
+ {
+ tree type = TREE_TYPE (ssa);
+ range_operator *op = range_op_handler (POINTER_PLUS_EXPR,
+ type);
+ int_range<2> offset (TREE_OPERAND (base, 1),
+ TREE_OPERAND (base, 1));
+ op->fold_range (r, type, range1, offset);
+ return true;
+ }
+ }
+ return false;
}
- /* If &X->a is equal to X, the range of X is the result. */
- if (off_cst && known_eq (off, 0))
- return true;
- else if (flag_delete_null_pointer_checks
- && !TYPE_OVERFLOW_WRAPS (TREE_TYPE (expr)))
- {
- /* For -fdelete-null-pointer-checks -fno-wrapv-pointer we don't
- allow going from non-NULL pointer to NULL. */
- if(!range_includes_zero_p (&r))
- return true;
- }
- /* If MEM_REF has a "positive" offset, consider it non-NULL
- always, for -fdelete-null-pointer-checks also "negative"
- ones. Punt for unknown offsets (e.g. variable ones). */
- if (!TYPE_OVERFLOW_WRAPS (TREE_TYPE (expr))
- && off_cst
- && known_ne (off, 0)
- && (flag_delete_null_pointer_checks || known_gt (off, 0)))
+ if (gimple_assign_rhs_code (stmt) == ADDR_EXPR)
{
+ // Handle "= &a" and return non-zero.
r = range_nonzero (TREE_TYPE (gimple_assign_rhs1 (stmt)));
return true;
}
- r = int_range<2> (TREE_TYPE (gimple_assign_rhs1 (stmt)));
- return true;
- }
-
- // Handle "= &a".
- if (tree_single_nonzero_warnv_p (expr, &strict_overflow_p))
- {
- r = range_nonzero (TREE_TYPE (gimple_assign_rhs1 (stmt)));
- return true;
}
-
- // Otherwise return varying.
- r = int_range<2> (TREE_TYPE (gimple_assign_rhs1 (stmt)));
- return true;
+ return false;
}
// Calculate a range for phi statement S and return it in R.
--- a/gcc/gimple-range.h
+++ b/gcc/gimple-range.h
@@ -62,7 +62,7 @@ protected:
ranger_cache m_cache;
private:
bool range_of_phi (irange &r, gphi *phi);
- bool range_of_address (irange &r, gimple *s);
+ bool range_of_non_trivial_assignment (irange &r, gimple *s);
bool range_of_builtin_call (irange &r, gcall *call);
bool range_with_loop_info (irange &r, tree name);
void range_of_ssa_name_with_loop_info (irange &, tree, class loop *,
--- a/gcc/range-op.cc
+++ b/gcc/range-op.cc
@@ -3447,7 +3447,6 @@ pointer_table::pointer_table ()
set (GT_EXPR, op_gt);
set (GE_EXPR, op_ge);
set (SSA_NAME, op_identity);
- set (INTEGER_CST, op_integer_cst);
set (ADDR_EXPR, op_addr);
set (NOP_EXPR, op_convert);
set (CONVERT_EXPR, op_convert);