From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2153) id AE0343858401; Tue, 17 Jan 2023 11:19:03 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org AE0343858401 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1673954343; bh=0yURI2+oAd8LI0xJjAeDsMclFedqkB3FP4hLSyNy4rU=; h=From:To:Subject:Date:From; b=ZLLqXHyePNf8SXu5BdwLExthi8hx4nBX1pZ8u4C4AlHZZVpfu2FnYonWMwl+GfX3H UfxizullUDAEb40VYm0DNNmOD5KJx0U1q8vMxI8f+nS6wQVPtHM9U901f0iu7kRuln pziOX7RiuYLW5RYY9nkzgJZAFmexaS+eCrAlaUPU= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jakub Jelinek To: gcc-cvs@gcc.gnu.org Subject: [gcc r13-5223] forwprop: Fix up rotate pattern matching [PR106523] X-Act-Checkin: gcc X-Git-Author: Jakub Jelinek X-Git-Refname: refs/heads/master X-Git-Oldrev: 85b45cccdf5f2442e791969abbffffbb2676591f X-Git-Newrev: 001121e8921d5d1a439ce0e64ab04c5959b0bfd8 Message-Id: <20230117111903.AE0343858401@sourceware.org> Date: Tue, 17 Jan 2023 11:19:03 +0000 (GMT) List-Id: https://gcc.gnu.org/g:001121e8921d5d1a439ce0e64ab04c5959b0bfd8 commit r13-5223-g001121e8921d5d1a439ce0e64ab04c5959b0bfd8 Author: Jakub Jelinek Date: Tue Jan 17 12:14:25 2023 +0100 forwprop: Fix up rotate pattern matching [PR106523] The comment above simplify_rotate roughly describes what patterns are matched into what: We are looking for X with unsigned type T with bitsize B, OP being +, | or ^, some type T2 wider than T. For: (X << CNT1) OP (X >> CNT2) iff CNT1 + CNT2 == B ((T) ((T2) X << CNT1)) OP ((T) ((T2) X >> CNT2)) iff CNT1 + CNT2 == B transform these into: X r<< CNT1 Or for: (X << Y) OP (X >> (B - Y)) (X << (int) Y) OP (X >> (int) (B - Y)) ((T) ((T2) X << Y)) OP ((T) ((T2) X >> (B - Y))) ((T) ((T2) X << (int) Y)) OP ((T) ((T2) X >> (int) (B - Y))) (X << Y) | (X >> ((-Y) & (B - 1))) (X << (int) Y) | (X >> (int) ((-Y) & (B - 1))) ((T) ((T2) X << Y)) | ((T) ((T2) X >> ((-Y) & (B - 1)))) ((T) ((T2) X << (int) Y)) | ((T) ((T2) X >> (int) ((-Y) & (B - 1)))) transform these into (last 2 only if ranger can prove Y < B): X r<< Y Or for: (X << (Y & (B - 1))) | (X >> ((-Y) & (B - 1))) (X << (int) (Y & (B - 1))) | (X >> (int) ((-Y) & (B - 1))) ((T) ((T2) X << (Y & (B - 1)))) | ((T) ((T2) X >> ((-Y) & (B - 1)))) ((T) ((T2) X << (int) (Y & (B - 1)))) \ | ((T) ((T2) X >> (int) ((-Y) & (B - 1)))) transform these into: X r<< (Y & (B - 1)) The following testcase shows that 2 of these are problematic. If T2 is wider than T, then the 2 which yse (-Y) & (B - 1) on one of the shift counts but Y on the can do something different from rotate. E.g.: __attribute__((noipa)) unsigned char f7 (unsigned char x, unsigned int y) { unsigned int t = x; return (t << y) | (t >> ((-y) & 7)); } if y is [0, 7], then it is a normal rotate, and if y is in [32, ~0U] then it is UB, but for y in [9, 31] the left shift in this case will never leave any bits in the result, while in a rotate they are left there. Say for y 5 and x 0xaa the expression gives 0x55 which is the same thing as rotate, while for y 19 and x 0xaa 0x5, which is different. Now, I believe the ((T) ((T2) X << Y)) OP ((T) ((T2) X >> (B - Y))) ((T) ((T2) X << (int) Y)) OP ((T) ((T2) X >> (int) (B - Y))) forms are ok, because B - Y still needs to be a valid shift count, and if Y > B then B - Y should be either negative or very large positive (for unsigned types). And similarly the last 2 cases above which use & (B - 1) on both shift operands are definitely ok. The following patch disables the ((T) ((T2) X << Y)) | ((T) ((T2) X >> ((-Y) & (B - 1)))) ((T) ((T2) X << (int) Y)) | ((T) ((T2) X >> (int) ((-Y) & (B - 1)))) unless ranger says Y is not in [B, B2 - 1] range. And, looking at it again this morning, actually the Y equal to B case is still fine, if Y is equal to 0, then it is (T) (((T2) X << 0) | ((T2) X >> 0)) and so X, for Y == B it is (T) (((T2) X << B) | ((T2) X >> 0)) which is the same as (T) (0 | ((T2) X >> 0)) which is also X. So instead of the [B, B2 - 1] range we could use [B + 1, B2 - 1]. And, if we wanted to go further, even multiplies of B are ok if they are smaller than B2, so we could construct a detailed int_range_max if we wanted. 2023-01-17 Jakub Jelinek PR tree-optimization/106523 * tree-ssa-forwprop.cc (simplify_rotate): For the patterns with (-Y) & (B - 1) in one operand's shift count and Y in another, if T2 has wider precision than T, punt if Y could have a value in [B, B2 - 1] range. * c-c++-common/rotate-2.c (f5, f6, f7, f8, f13, f14, f15, f16, f37, f38, f39, f40, f45, f46, f47, f48): Add assertions using __builtin_unreachable about shift count. * c-c++-common/rotate-2b.c: New test. * c-c++-common/rotate-4.c (f5, f6, f7, f8, f13, f14, f15, f16, f37, f38, f39, f40, f45, f46, f47, f48): Add assertions using __builtin_unreachable about shift count. * c-c++-common/rotate-4b.c: New test. * gcc.c-torture/execute/pr106523.c: New test. Diff: --- gcc/testsuite/c-c++-common/rotate-2.c | 32 ++++++++ gcc/testsuite/c-c++-common/rotate-2b.c | 100 +++++++++++++++++++++++++ gcc/testsuite/c-c++-common/rotate-4.c | 32 ++++++++ gcc/testsuite/c-c++-common/rotate-4b.c | 100 +++++++++++++++++++++++++ gcc/testsuite/gcc.c-torture/execute/pr106523.c | 22 ++++++ gcc/tree-ssa-forwprop.cc | 53 ++++++++++++- 6 files changed, 335 insertions(+), 4 deletions(-) diff --git a/gcc/testsuite/c-c++-common/rotate-2.c b/gcc/testsuite/c-c++-common/rotate-2.c index c8359cd2ae0..544a7ca298f 100644 --- a/gcc/testsuite/c-c++-common/rotate-2.c +++ b/gcc/testsuite/c-c++-common/rotate-2.c @@ -32,24 +32,32 @@ f4 (unsigned int x, int y __attribute__((unused))) unsigned short int f5 (unsigned short int x, unsigned int y) { + if (y >= __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); } unsigned short int f6 (unsigned short int x, unsigned long int y) { + if (y >= __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); } unsigned char f7 (unsigned char x, unsigned int y) { + if (y >= __CHAR_BIT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ - 1))); } unsigned char f8 (unsigned char x, unsigned long int y) { + if (y >= __CHAR_BIT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ - 1))); } @@ -80,24 +88,32 @@ f12 (unsigned int x, int y __attribute__((unused))) unsigned short int f13 (unsigned short int x, unsigned int y) { + if (y >= __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); } unsigned short int f14 (unsigned short int x, unsigned long int y) { + if (y >= __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); } unsigned char f15 (unsigned char x, unsigned int y) { + if (y >= __CHAR_BIT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); } unsigned char f16 (unsigned char x, unsigned long int y) { + if (y >= __CHAR_BIT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); } @@ -224,24 +240,32 @@ f36 (unsigned int x, int y __attribute__((unused))) unsigned short int f37 (unsigned short int x, unsigned int y) { + if (y >= __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); } unsigned short int f38 (unsigned short int x, unsigned long int y) { + if (y >= __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); } unsigned char f39 (unsigned char x, unsigned int y) { + if (y >= __CHAR_BIT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ - 1))); } unsigned char f40 (unsigned char x, unsigned long int y) { + if (y >= __CHAR_BIT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ - 1))); } @@ -272,24 +296,32 @@ f44 (unsigned int x, int y __attribute__((unused))) unsigned short int f45 (unsigned short int x, unsigned int y) { + if (y >= __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); } unsigned short int f46 (unsigned short int x, unsigned long int y) { + if (y >= __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); } unsigned char f47 (unsigned char x, unsigned int y) { + if (y >= __CHAR_BIT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); } unsigned char f48 (unsigned char x, unsigned long int y) { + if (y >= __CHAR_BIT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); } diff --git a/gcc/testsuite/c-c++-common/rotate-2b.c b/gcc/testsuite/c-c++-common/rotate-2b.c new file mode 100644 index 00000000000..2a6bf909ae6 --- /dev/null +++ b/gcc/testsuite/c-c++-common/rotate-2b.c @@ -0,0 +1,100 @@ +/* Check rotate pattern detection. */ +/* { dg-do compile } */ +/* { dg-options "-O2 -fno-ipa-icf -fdump-tree-optimized" } */ +/* { dg-final { scan-tree-dump-not "r\[<>]\[<>]" "optimized" } } */ + +unsigned short int +f5 (unsigned short int x, unsigned int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); +} + +unsigned short int +f6 (unsigned short int x, unsigned long int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); +} + +unsigned char +f7 (unsigned char x, unsigned int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ - 1))); +} + +unsigned char +f8 (unsigned char x, unsigned long int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ - 1))); +} + +unsigned short int +f13 (unsigned short int x, unsigned int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); +} + +unsigned short int +f14 (unsigned short int x, unsigned long int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); +} + +unsigned char +f15 (unsigned char x, unsigned int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); +} + +unsigned char +f16 (unsigned char x, unsigned long int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); +} + +unsigned short int +f37 (unsigned short int x, unsigned int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); +} + +unsigned short int +f38 (unsigned short int x, unsigned long int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); +} + +unsigned char +f39 (unsigned char x, unsigned int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ - 1))); +} + +unsigned char +f40 (unsigned char x, unsigned long int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ - 1))); +} + +unsigned short int +f45 (unsigned short int x, unsigned int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); +} + +unsigned short int +f46 (unsigned short int x, unsigned long int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); +} + +unsigned char +f47 (unsigned char x, unsigned int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); +} + +unsigned char +f48 (unsigned char x, unsigned long int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); +} diff --git a/gcc/testsuite/c-c++-common/rotate-4.c b/gcc/testsuite/c-c++-common/rotate-4.c index 44fd1d0bb83..f85236239d8 100644 --- a/gcc/testsuite/c-c++-common/rotate-4.c +++ b/gcc/testsuite/c-c++-common/rotate-4.c @@ -32,24 +32,32 @@ f4 (unsigned int x, int y __attribute__((unused))) unsigned short int f5 (unsigned short int x, int y) { + if (y >= __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); } unsigned short int f6 (unsigned short int x, long int y) { + if (y >= 0UL + __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); } unsigned char f7 (unsigned char x, int y) { + if (y >= __CHAR_BIT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ - 1))); } unsigned char f8 (unsigned char x, long int y) { + if (y >= 0UL + __CHAR_BIT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ - 1))); } @@ -80,24 +88,32 @@ f12 (unsigned int x, int y __attribute__((unused))) unsigned short int f13 (unsigned short int x, int y) { + if (y >= __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); } unsigned short int f14 (unsigned short int x, long int y) { + if (y >= 0UL + __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); } unsigned char f15 (unsigned char x, int y) { + if (y >= __CHAR_BIT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); } unsigned char f16 (unsigned char x, long int y) { + if (y >= 0UL + __CHAR_BIT__) + __builtin_unreachable (); return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); } @@ -224,24 +240,32 @@ f36 (unsigned int x, int y __attribute__((unused))) unsigned short int f37 (unsigned short int x, int y) { + if (y >= __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); } unsigned short int f38 (unsigned short int x, long int y) { + if (y >= 0UL + __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); } unsigned char f39 (unsigned char x, int y) { + if (y >= __CHAR_BIT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ - 1))); } unsigned char f40 (unsigned char x, long int y) { + if (y >= 0UL + __CHAR_BIT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ - 1))); } @@ -272,24 +296,32 @@ f44 (unsigned int x, int y __attribute__((unused))) unsigned short int f45 (unsigned short int x, int y) { + if (y >= __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); } unsigned short int f46 (unsigned short int x, long int y) { + if (y >= 0UL + __CHAR_BIT__ * __SIZEOF_SHORT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); } unsigned char f47 (unsigned char x, int y) { + if (y >= __CHAR_BIT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); } unsigned char f48 (unsigned char x, long int y) { + if (y >= 0UL + __CHAR_BIT__) + __builtin_unreachable (); return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); } diff --git a/gcc/testsuite/c-c++-common/rotate-4b.c b/gcc/testsuite/c-c++-common/rotate-4b.c new file mode 100644 index 00000000000..a3824754d63 --- /dev/null +++ b/gcc/testsuite/c-c++-common/rotate-4b.c @@ -0,0 +1,100 @@ +/* Check rotate pattern detection. */ +/* { dg-do compile } */ +/* { dg-options "-O2 -fno-ipa-icf -fdump-tree-optimized" } */ +/* { dg-final { scan-tree-dump-not "r\[<>]\[<>]" "optimized" } } */ + +unsigned short int +f5 (unsigned short int x, int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); +} + +unsigned short int +f6 (unsigned short int x, long int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); +} + +unsigned char +f7 (unsigned char x, int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ - 1))); +} + +unsigned char +f8 (unsigned char x, long int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ - 1))); +} + +unsigned short int +f13 (unsigned short int x, int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); +} + +unsigned short int +f14 (unsigned short int x, long int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); +} + +unsigned char +f15 (unsigned char x, int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); +} + +unsigned char +f16 (unsigned char x, long int y) +{ + return (x << y) | (x >> ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); +} + +unsigned short int +f37 (unsigned short int x, int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); +} + +unsigned short int +f38 (unsigned short int x, long int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * __SIZEOF_SHORT__ - 1))); +} + +unsigned char +f39 (unsigned char x, int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ - 1))); +} + +unsigned char +f40 (unsigned char x, long int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ - 1))); +} + +unsigned short int +f45 (unsigned short int x, int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); +} + +unsigned short int +f46 (unsigned short int x, long int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned short) - 1))); +} + +unsigned char +f47 (unsigned char x, int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); +} + +unsigned char +f48 (unsigned char x, long int y) +{ + return (x >> y) | (x << ((-y) & (__CHAR_BIT__ * sizeof (unsigned char) - 1))); +} diff --git a/gcc/testsuite/gcc.c-torture/execute/pr106523.c b/gcc/testsuite/gcc.c-torture/execute/pr106523.c new file mode 100644 index 00000000000..abd78f59ce3 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/pr106523.c @@ -0,0 +1,22 @@ +/* PR tree-optimization/106523 */ + +__attribute__((noipa)) unsigned char +f7 (unsigned char x, unsigned int y) +{ + unsigned int t = x; + return (t << y) | (t >> ((-y) & 7)); +} + +int +main () +{ + if (__CHAR_BIT__ != 8 || __SIZEOF_INT__ != 4) + return 0; + + volatile unsigned char x = 152; + volatile unsigned int y = 19; + if (f7 (x, y) != 4) + __builtin_abort (); + + return 0; +} diff --git a/gcc/tree-ssa-forwprop.cc b/gcc/tree-ssa-forwprop.cc index 0a7e95683ce..458d9c8e483 100644 --- a/gcc/tree-ssa-forwprop.cc +++ b/gcc/tree-ssa-forwprop.cc @@ -1837,7 +1837,7 @@ defcodefor_name (tree name, enum tree_code *code, tree *arg1, tree *arg2) ((T) ((T2) X << Y)) | ((T) ((T2) X >> ((-Y) & (B - 1)))) ((T) ((T2) X << (int) Y)) | ((T) ((T2) X >> (int) ((-Y) & (B - 1)))) - transform these into: + transform these into (last 2 only if ranger can prove Y < B): X r<< Y Or for: @@ -1866,6 +1866,8 @@ simplify_rotate (gimple_stmt_iterator *gsi) int i; bool swapped_p = false; gimple *g; + gimple *def_arg_stmt[2] = { NULL, NULL }; + int wider_prec = 0; arg[0] = gimple_assign_rhs1 (stmt); arg[1] = gimple_assign_rhs2 (stmt); @@ -1878,7 +1880,11 @@ simplify_rotate (gimple_stmt_iterator *gsi) return false; for (i = 0; i < 2; i++) - defcodefor_name (arg[i], &def_code[i], &def_arg1[i], &def_arg2[i]); + { + defcodefor_name (arg[i], &def_code[i], &def_arg1[i], &def_arg2[i]); + if (TREE_CODE (arg[i]) == SSA_NAME) + def_arg_stmt[i] = SSA_NAME_DEF_STMT (arg[i]); + } /* Look through narrowing (or same precision) conversions. */ if (CONVERT_EXPR_CODE_P (def_code[0]) @@ -1891,10 +1897,13 @@ simplify_rotate (gimple_stmt_iterator *gsi) && has_single_use (arg[0]) && has_single_use (arg[1])) { + wider_prec = TYPE_PRECISION (TREE_TYPE (def_arg1[0])); for (i = 0; i < 2; i++) { arg[i] = def_arg1[i]; defcodefor_name (arg[i], &def_code[i], &def_arg1[i], &def_arg2[i]); + if (TREE_CODE (arg[i]) == SSA_NAME) + def_arg_stmt[i] = SSA_NAME_DEF_STMT (arg[i]); } } else @@ -1910,6 +1919,8 @@ simplify_rotate (gimple_stmt_iterator *gsi) { arg[i] = def_arg1[i]; defcodefor_name (arg[i], &def_code[i], &def_arg1[i], &def_arg2[i]); + if (TREE_CODE (arg[i]) == SSA_NAME) + def_arg_stmt[i] = SSA_NAME_DEF_STMT (arg[i]); } } @@ -1983,6 +1994,9 @@ simplify_rotate (gimple_stmt_iterator *gsi) { tree cdef_arg1[2], cdef_arg2[2], def_arg2_alt[2]; enum tree_code cdef_code[2]; + gimple *def_arg_alt_stmt[2] = { NULL, NULL }; + bool check_range = false; + gimple *check_range_stmt = NULL; /* Look through conversion of the shift count argument. The C/C++ FE cast any shift count argument to integer_type_node. The only problem might be if the shift count type maximum value @@ -1999,9 +2013,13 @@ simplify_rotate (gimple_stmt_iterator *gsi) && type_has_mode_precision_p (TREE_TYPE (cdef_arg1[i]))) { def_arg2_alt[i] = cdef_arg1[i]; + if (TREE_CODE (def_arg2[i]) == SSA_NAME) + def_arg_alt_stmt[i] = SSA_NAME_DEF_STMT (def_arg2[i]); defcodefor_name (def_arg2_alt[i], &cdef_code[i], &cdef_arg1[i], &cdef_arg2[i]); } + else + def_arg_alt_stmt[i] = def_arg_stmt[i]; } for (i = 0; i < 2; i++) /* Check for one shift count being Y and the other B - Y, @@ -2024,7 +2042,7 @@ simplify_rotate (gimple_stmt_iterator *gsi) if (CONVERT_EXPR_CODE_P (code) && INTEGRAL_TYPE_P (TREE_TYPE (tem)) && TYPE_PRECISION (TREE_TYPE (tem)) - > floor_log2 (TYPE_PRECISION (rtype)) + > floor_log2 (TYPE_PRECISION (rtype)) && type_has_mode_precision_p (TREE_TYPE (tem)) && (tem == def_arg2[1 - i] || tem == def_arg2_alt[1 - i])) @@ -2053,7 +2071,7 @@ simplify_rotate (gimple_stmt_iterator *gsi) if (CONVERT_EXPR_CODE_P (code) && INTEGRAL_TYPE_P (TREE_TYPE (tem)) && TYPE_PRECISION (TREE_TYPE (tem)) - > floor_log2 (TYPE_PRECISION (rtype)) + > floor_log2 (TYPE_PRECISION (rtype)) && type_has_mode_precision_p (TREE_TYPE (tem))) defcodefor_name (tem, &code, &tem, NULL); @@ -2062,6 +2080,11 @@ simplify_rotate (gimple_stmt_iterator *gsi) if (tem == def_arg2[1 - i] || tem == def_arg2_alt[1 - i]) { rotcnt = tem; + check_range = true; + if (tem == def_arg2[1 - i]) + check_range_stmt = def_arg_stmt[1 - i]; + else + check_range_stmt = def_arg_alt_stmt[1 - i]; break; } tree tem2; @@ -2076,6 +2099,11 @@ simplify_rotate (gimple_stmt_iterator *gsi) || tem2 == def_arg2_alt[1 - i]) { rotcnt = tem2; + check_range = true; + if (tem2 == def_arg2[1 - i]) + check_range_stmt = def_arg_stmt[1 - i]; + else + check_range_stmt = def_arg_alt_stmt[1 - i]; break; } } @@ -2111,6 +2139,23 @@ simplify_rotate (gimple_stmt_iterator *gsi) } } } + if (check_range && wider_prec > TYPE_PRECISION (rtype)) + { + if (TREE_CODE (rotcnt) != SSA_NAME) + return false; + int_range_max r; + if (!get_global_range_query ()->range_of_expr (r, rotcnt, + check_range_stmt)) + return false; + int prec = TYPE_PRECISION (TREE_TYPE (rotcnt)); + signop sign = TYPE_SIGN (TREE_TYPE (rotcnt)); + wide_int min = wide_int::from (TYPE_PRECISION (rtype), prec, sign); + wide_int max = wide_int::from (wider_prec - 1, prec, sign); + int_range<2> r2 (TREE_TYPE (rotcnt), min, max); + r.intersect (r2); + if (!r.undefined_p ()) + return false; + } if (rotcnt == NULL_TREE) return false; swapped_p = i != 1;