From bb6d88ec0f032479105ffa0c10231ef35cf36a99 Mon Sep 17 00:00:00 2001 From: Peter Korsgaard Date: Tue, 10 Mar 2009 22:01:06 +0000 Subject: gcc: 4.3.x fix for PR 32044. Patch by Daniel Mack --- .../gcc/4.3.1/901-backport-fix-for-bug-32044.patch | 193 +++++++++++++++++++++ 1 file changed, 193 insertions(+) create mode 100644 toolchain/gcc/4.3.1/901-backport-fix-for-bug-32044.patch (limited to 'toolchain/gcc/4.3.1') diff --git a/toolchain/gcc/4.3.1/901-backport-fix-for-bug-32044.patch b/toolchain/gcc/4.3.1/901-backport-fix-for-bug-32044.patch new file mode 100644 index 000000000..603c7f698 --- /dev/null +++ b/toolchain/gcc/4.3.1/901-backport-fix-for-bug-32044.patch @@ -0,0 +1,193 @@ +Index: toolchain/gcc/4.3.2/901-backport-fix-for-bug-32044.patch +=================================================================== +--- toolchain/gcc/4.3.2/901-backport-fix-for-bug-32044.patch (revision 0) ++++ toolchain/gcc/4.3.2/901-backport-fix-for-bug-32044.patch (revision 0) +@@ -0,0 +1,188 @@ ++Index: gcc-4.3.2/gcc/tree-scalar-evolution.c ++=================================================================== ++--- gcc-4.3.2.orig/gcc/tree-scalar-evolution.c 2009-01-28 10:14:37.000000000 +0100 +++++ gcc-4.3.2/gcc/tree-scalar-evolution.c 2009-01-28 10:17:50.000000000 +0100 ++@@ -2716,6 +2716,50 @@ ++ scalar_evolution_info = NULL; ++ } ++ +++/* Returns true if the expression EXPR is considered to be too expensive +++ for scev_const_prop. */ +++ +++bool +++expression_expensive_p (tree expr) +++{ +++ enum tree_code code; +++ +++ if (is_gimple_val (expr)) +++ return false; +++ +++ code = TREE_CODE (expr); +++ if (code == TRUNC_DIV_EXPR +++ || code == CEIL_DIV_EXPR +++ || code == FLOOR_DIV_EXPR +++ || code == ROUND_DIV_EXPR +++ || code == TRUNC_MOD_EXPR +++ || code == CEIL_MOD_EXPR +++ || code == FLOOR_MOD_EXPR +++ || code == ROUND_MOD_EXPR +++ || code == EXACT_DIV_EXPR) +++ { +++ /* Division by power of two is usually cheap, so we allow it. +++ Forbid anything else. */ +++ if (!integer_pow2p (TREE_OPERAND (expr, 1))) +++ return true; +++ } +++ +++ switch (TREE_CODE_CLASS (code)) +++ { +++ case tcc_binary: +++ case tcc_comparison: +++ if (expression_expensive_p (TREE_OPERAND (expr, 1))) +++ return true; +++ +++ /* Fallthru. */ +++ case tcc_unary: +++ return expression_expensive_p (TREE_OPERAND (expr, 0)); +++ +++ default: +++ return true; +++ } +++} +++ ++ /* Replace ssa names for that scev can prove they are constant by the ++ appropriate constants. Also perform final value replacement in loops, ++ in case the replacement expressions are cheap. ++@@ -2802,12 +2846,6 @@ ++ continue; ++ ++ niter = number_of_latch_executions (loop); ++- /* We used to check here whether the computation of NITER is expensive, ++- and avoided final value elimination if that is the case. The problem ++- is that it is hard to evaluate whether the expression is too ++- expensive, as we do not know what optimization opportunities the ++- the elimination of the final value may reveal. Therefore, we now ++- eliminate the final values of induction variables unconditionally. */ ++ if (niter == chrec_dont_know) ++ continue; ++ ++@@ -2838,7 +2876,15 @@ ++ /* Moving the computation from the loop may prolong life range ++ of some ssa names, which may cause problems if they appear ++ on abnormal edges. */ ++- || contains_abnormal_ssa_name_p (def)) +++ || contains_abnormal_ssa_name_p (def) +++ /* Do not emit expensive expressions. The rationale is that +++ when someone writes a code like +++ +++ while (n > 45) n -= 45; +++ +++ he probably knows that n is not large, and does not want it +++ to be turned into n %= 45. */ +++ || expression_expensive_p (def)) ++ continue; ++ ++ /* Eliminate the PHI node and replace it by a computation outside ++Index: gcc-4.3.2/gcc/tree-scalar-evolution.h ++=================================================================== ++--- gcc-4.3.2.orig/gcc/tree-scalar-evolution.h 2009-01-28 10:22:47.000000000 +0100 +++++ gcc-4.3.2/gcc/tree-scalar-evolution.h 2009-01-28 10:23:10.000000000 +0100 ++@@ -35,6 +35,7 @@ ++ extern void scev_analysis (void); ++ unsigned int scev_const_prop (void); ++ +++bool expression_expensive_p (tree); ++ extern bool simple_iv (struct loop *, tree, tree, affine_iv *, bool); ++ ++ /* Returns the loop of the polynomial chrec CHREC. */ ++Index: gcc-4.3.2/gcc/testsuite/gcc.dg/pr34027-1.c ++=================================================================== ++--- gcc-4.3.2.orig/gcc/testsuite/gcc.dg/pr34027-1.c 2009-01-28 10:24:09.000000000 +0100 +++++ gcc-4.3.2/gcc/testsuite/gcc.dg/pr34027-1.c 2009-01-28 10:24:43.000000000 +0100 ++@@ -8,5 +8,9 @@ ++ return ns; ++ } ++ ++-/* { dg-final { scan-tree-dump "ns % 10000" "optimized" } } */ +++/* This test was originally introduced to test that we transform +++ to ns % 10000. See the discussion of PR 32044 why we do not do +++ that anymore. */ +++/* { dg-final { scan-tree-dump-times "%" 0 "optimized" } } */ +++/* { dg-final { scan-tree-dump-times "/" 0 "optimized" } } */ ++ /* { dg-final { cleanup-tree-dump "optimized" } } */ ++Index: gcc-4.3.2/gcc/testsuite/gcc.dg/tree-ssa/pr32044.c ++=================================================================== ++--- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++++ gcc-4.3.2/gcc/testsuite/gcc.dg/tree-ssa/pr32044.c 2009-01-28 10:25:50.000000000 +0100 ++@@ -0,0 +1,55 @@ +++/* { dg-do compile } */ +++/* { dg-options "-O2 -fdump-tree-empty -fdump-tree-final_cleanup" } */ +++ +++int foo (int n) +++{ +++ while (n >= 45) +++ n -= 45; +++ +++ return n; +++} +++ +++int bar (int n) +++{ +++ while (n >= 64) +++ n -= 64; +++ +++ return n; +++} +++ +++int bla (int n) +++{ +++ int i = 0; +++ +++ while (n >= 45) +++ { +++ i++; +++ n -= 45; +++ } +++ +++ return i; +++} +++ +++int baz (int n) +++{ +++ int i = 0; +++ +++ while (n >= 64) +++ { +++ i++; +++ n -= 64; +++ } +++ +++ return i; +++} +++ +++/* The loops computing division/modulo by 64 should be eliminated. */ +++/* { dg-final { scan-tree-dump-times "Removing empty loop" 2 "empty" } } */ +++ +++/* There should be no division/modulo in the final dump (division and modulo +++ by 64 are done using bit operations). */ +++/* { dg-final { scan-tree-dump-times "/" 0 "final_cleanup" } } */ +++/* { dg-final { scan-tree-dump-times "%" 0 "final_cleanup" } } */ +++ +++/* { dg-final { cleanup-tree-dump "empty" } } */ +++/* { dg-final { cleanup-tree-dump "final_cleanup" } } */ ++Index: gcc-4.3.2/gcc/tree-ssa-loop-ivopts.c ++=================================================================== ++--- gcc-4.3.2.orig/gcc/tree-ssa-loop-ivopts.c 2009-01-28 10:26:04.000000000 +0100 +++++ gcc-4.3.2/gcc/tree-ssa-loop-ivopts.c 2009-01-28 10:27:09.000000000 +0100 ++@@ -3778,7 +3778,12 @@ ++ return false; ++ ++ cand_value_at (loop, cand, use->stmt, nit, &bnd); +++ ++ *bound = aff_combination_to_tree (&bnd); +++ /* It is unlikely that computing the number of iterations using division +++ would be more profitable than keeping the original induction variable. */ +++ if (expression_expensive_p (*bound)) +++ return false; ++ return true; ++ } -- cgit v1.2.3