diff options
author | Richard Henderson <rth@redhat.com> | 2016-02-01 07:32:01 +0000 |
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committer | Richard Henderson <rth@redhat.com> | 2016-02-01 07:32:01 +0000 |
commit | bf25f6a3b7c2d006317668ac7af7c8013804106c (patch) | |
tree | 1a823e636b4518bcd0082dd43b0cca0e2f504118 | |
parent | f8ad52eb9d0acc2b494894f88c7cf63c316ca7c6 (diff) |
PR rtl-opt/69535
* combine.c (make_compound_operation): When looking through a
subreg, make sure to re-extend to the width of the outer mode.
git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@233032 138bc75d-0d04-0410-961f-82ee72b054a4
-rw-r--r-- | gcc/ChangeLog | 6 | ||||
-rw-r--r-- | gcc/combine.c | 24 | ||||
-rw-r--r-- | gcc/testsuite/ChangeLog | 4 | ||||
-rw-r--r-- | gcc/testsuite/gcc.dg/pr69535.c | 36 |
4 files changed, 65 insertions, 5 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 0d405cdcbd5..bf63f26202d 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2016-02-01 Richard Henderson <rth@redhat.com> + + PR rtl-opt/69535 + * combine.c (make_compound_operation): When looking through a + subreg, make sure to re-extend to the width of the outer mode. + 2016-01-30 Jakub Jelinek <jakub@redhat.com> PR tree-optimization/69546 diff --git a/gcc/combine.c b/gcc/combine.c index 858552ddc3f..c307793a495 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -7887,11 +7887,25 @@ make_compound_operation (rtx x, enum rtx_code in_code) && GET_CODE (SUBREG_REG (XEXP (x, 0))) == LSHIFTRT && (i = exact_log2 (UINTVAL (XEXP (x, 1)) + 1)) >= 0) { - new_rtx = make_compound_operation (XEXP (SUBREG_REG (XEXP (x, 0)), 0), - next_code); - new_rtx = make_extraction (GET_MODE (SUBREG_REG (XEXP (x, 0))), new_rtx, 0, - XEXP (SUBREG_REG (XEXP (x, 0)), 1), i, 1, - 0, in_code == COMPARE); + rtx inner_x0 = SUBREG_REG (XEXP (x, 0)); + machine_mode inner_mode = GET_MODE (inner_x0); + new_rtx = make_compound_operation (XEXP (inner_x0, 0), next_code); + new_rtx = make_extraction (inner_mode, new_rtx, 0, + XEXP (inner_x0, 1), + i, 1, 0, in_code == COMPARE); + + if (new_rtx) + { + /* If we narrowed the mode when dropping the subreg, then + we must zero-extend to keep the semantics of the AND. */ + if (GET_MODE_SIZE (inner_mode) >= GET_MODE_SIZE (mode)) + ; + else if (SCALAR_INT_MODE_P (inner_mode)) + new_rtx = simplify_gen_unary (ZERO_EXTEND, mode, + new_rtx, inner_mode); + else + new_rtx = NULL; + } /* If that didn't give anything, see if the AND simplifies on its own. */ diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 168a74d406d..d05a689e7b2 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2016-02-01 Richard Henderson <rth@redhat.com> + + * gcc.dg/pr69535.c: New test. + 2016-01-31 John David Anglin <danglin@gcc.gnu.org> PR testsuite/69584 diff --git a/gcc/testsuite/gcc.dg/pr69535.c b/gcc/testsuite/gcc.dg/pr69535.c new file mode 100644 index 00000000000..4b4dad154da --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr69535.c @@ -0,0 +1,36 @@ +/* { dg-do run { target int128 } } */ +/* { dg-options "-O -fno-tree-bit-ccp -fno-tree-reassoc" } */ + +typedef unsigned char u8; +typedef unsigned short u16; +typedef unsigned int u32; +typedef unsigned long long u64; +typedef unsigned __int128 u128; + +void __attribute__((noinline, noclone)) +dirtify_stack(void) +{ + volatile char a[] = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" + "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" + "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" + "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"; +} + +u128 __attribute__ ((noinline, noclone)) +foo(u32 u32_1, u64 u64_1, u128 u128_1, u8 u8_2, u16 u16_2, u32 u32_2, u8 u8_3) +{ + u128_1 /= ~u128_1 | 1; + u8_3 = ((u8_3 << 2) >> 1) << 7; + u32_2 >>= u8_3; + return u128_1 + u32_2 + u8_3; +} + +int +main () +{ + dirtify_stack(); + u128 x = foo(1, 1, 1, 1, 1, 1, 0); + if (x != 1) + __builtin_abort(); + return 0; +} |