Hi!
extract_muldiv{,_1} is apparently only prepared to handle scalar integer
operations, the callers ensure it by only calling it if the divisor or
one of the multiplicands is INTEGER_CST and because neither multiplication
nor division nor modulo are really supported e.g. for pointer types, nullptr
type etc. But the CASE_CONVERT handling doesn't really check if it isn't
a cast from some other type kind, so on the testcase we end up trying to
build MULT_EXPR in POINTER_TYPE which ICEs. A few years ago Marek has
added ANY_INTEGRAL_TYPE_P checks to two spots, but the code uses
TYPE_PRECISION which means something completely different for vector types,
etc.
So IMNSHO we should just punt on conversions from non-integrals or
non-scalar integrals.
Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for
trunk?
2021-03-26 Jakub Jelinek <ja...@redhat.com>
PR tree-optimization/99777
* fold-const.c (extract_muldiv_1): For conversions, punt on casts from
types other than scalar integral types.
* g++.dg/torture/pr99777.C: New test.
--- gcc/fold-const.c.jj 2021-03-25 13:41:55.000000000 +0100
+++ gcc/fold-const.c 2021-03-26 11:51:57.901091895 +0100
@@ -6713,6 +6713,8 @@ extract_muldiv_1 (tree t, tree c, enum t
break;
CASE_CONVERT: case NON_LVALUE_EXPR:
+ if (!INTEGRAL_TYPE_P (TREE_TYPE (op0)))
+ break;
/* If op0 is an expression ... */
if ((COMPARISON_CLASS_P (op0)
|| UNARY_CLASS_P (op0)
@@ -6721,8 +6723,7 @@ extract_muldiv_1 (tree t, tree c, enum t
|| EXPRESSION_CLASS_P (op0))
/* ... and has wrapping overflow, and its type is smaller
than ctype, then we cannot pass through as widening. */
- && (((ANY_INTEGRAL_TYPE_P (TREE_TYPE (op0))
- && TYPE_OVERFLOW_WRAPS (TREE_TYPE (op0)))
+ && ((TYPE_OVERFLOW_WRAPS (TREE_TYPE (op0))
&& (TYPE_PRECISION (ctype)
> TYPE_PRECISION (TREE_TYPE (op0))))
/* ... or this is a truncation (t is narrower than op0),
@@ -6737,8 +6738,7 @@ extract_muldiv_1 (tree t, tree c, enum t
/* ... or has undefined overflow while the converted to
type has not, we cannot do the operation in the inner type
as that would introduce undefined overflow. */
- || ((ANY_INTEGRAL_TYPE_P (TREE_TYPE (op0))
- && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (op0)))
+ || (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (op0))
&& !TYPE_OVERFLOW_UNDEFINED (type))))
break;
--- gcc/testsuite/g++.dg/torture/pr99777.C.jj 2021-03-26 12:22:49.833560450
+0100
+++ gcc/testsuite/g++.dg/torture/pr99777.C 2021-03-26 12:22:37.927692142
+0100
@@ -0,0 +1,44 @@
+// PR tree-optimization/99777
+
+template <typename T>
+inline const T &
+min (const T &a, const T &b)
+{
+ if (b < a)
+ return b;
+ return a;
+}
+
+template <typename T>
+inline const T &
+max (const T &a, const T &b)
+{
+ if (a < b)
+ return b;
+ return a;
+}
+
+extern int o, a, c;
+long h;
+unsigned long long e;
+signed char d;
+extern short p[][7][5][30];
+
+void
+test (long long b, short f[][17][25][22][20])
+{
+ for (char i = 0; i < 7; i += 3)
+ for (unsigned char l = e; l < 5; l += 2)
+ {
+ if (max (0LL, min (7LL, b)))
+ for (bool j = 0; j < 1; j = b)
+ {
+ for (unsigned k = d; k < 20; k++)
+ h = f[0][i][l][b][k];
+ for (int m = 0; m < 5; m++)
+ p[c][i][l][m] = 0;
+ }
+ for (int n = 0; n < 4; n += a)
+ o = n;
+ }
+}
Jakub
