From 4808997182f59d6807021f19bc92eaaaa94a29b1 Mon Sep 17 00:00:00 2001 From: rguenth Date: Wed, 4 Jul 2012 12:10:40 +0000 Subject: [PATCH] 2012-07-04 Richard Guenther PR tree-optimization/53844 * tree-ssa-dse.c (dse_possible_dead_store_p): Properly handle the loop virtual PHI. * g++.dg/tree-ssa/pr53844.C: New testcase. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@189256 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/ChangeLog | 6 +++ gcc/testsuite/ChangeLog | 5 +++ gcc/testsuite/g++.dg/tree-ssa/pr53844.C | 78 +++++++++++++++++++++++++++++++++ gcc/tree-ssa-dse.c | 12 ++++- 4 files changed, 99 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/g++.dg/tree-ssa/pr53844.C diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 27c8cfc..c33c5a5 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,11 @@ 2012-07-04 Richard Guenther + PR tree-optimization/53844 + * tree-ssa-dse.c (dse_possible_dead_store_p): Properly handle + the loop virtual PHI. + +2012-07-04 Richard Guenther + PR tree-optimization/53849 * tree-cfg.c (move_stmt_op): Only call add_referenced_var for duplicated locals. Use add_referenced_var_1 to avoid diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 884f66b..3d1fda9 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,5 +1,10 @@ 2012-07-04 Richard Guenther + PR tree-optimization/53844 + * g++.dg/tree-ssa/pr53844.C: New testcase. + +2012-07-04 Richard Guenther + PR tree-optimization/53849 * gcc.dg/pr53849.c: New testcase. diff --git a/gcc/testsuite/g++.dg/tree-ssa/pr53844.C b/gcc/testsuite/g++.dg/tree-ssa/pr53844.C new file mode 100644 index 0000000..0be29d8 --- /dev/null +++ b/gcc/testsuite/g++.dg/tree-ssa/pr53844.C @@ -0,0 +1,78 @@ +// { dg-do compile } +// { dg-options "-O2 -fdump-tree-optimized-vops" } + +struct VBase; + +//Very minimal numeric vector class where Base provides the policy +template +struct Vector : public Base{ + + inline Vector(const Base& b) + :Base(b) + { + } + + //Assignment from any other sort of Vector + template + void operator= (const Vector& from) + { + for(int i=0; i<100; i++){ + (*this)[i]=from[i]; + } + } +}; + + +//Base class to represent pointer as a Vector +struct VBase{ + double * const my_data; + + double& operator[](int i) { + return my_data[i]; + } + + const double& operator[](int i) const { + return my_data[i]; + } +}; + +//Base class providing very minimalistic expression template +template struct ScalarMulExpr +{ + const int& mul; + const Vector& vec; + + int size() const + { + return vec.size(); + } + + double operator[](int i) const + { + return vec[i]*mul; + } + + ScalarMulExpr(const Vector& vec_, const int& m) + :mul(m),vec(vec_) + { + } +}; + +//Allow vector to be multiplied by a scalar +template +Vector > operator*(const Vector& lhs, const int& rhs) +{ + return ScalarMulExpr(lhs, rhs); +} + +//Test function producing suboptimal asm code +void test(const Vector<>& in, Vector<>& out, int i) +{ + out=in*1*1*1*1*1*1*1*1*1*1*1; +} + +// There should be a single store remaining, inside the loops. All +// dead stores to unused temporaries should have been removed. + +// { dg-final { scan-tree-dump-times "VDEF" 1 "optimized" } } +// { dg-final { cleanup-tree-dump "optimized" } } diff --git a/gcc/tree-ssa-dse.c b/gcc/tree-ssa-dse.c index 5fdba8c..04cc6ad 100644 --- a/gcc/tree-ssa-dse.c +++ b/gcc/tree-ssa-dse.c @@ -94,7 +94,7 @@ dse_possible_dead_store_p (gimple stmt, gimple *use_stmt) temp = stmt; do { - gimple use_stmt; + gimple use_stmt, defvar_def; imm_use_iterator ui; bool fail = false; tree defvar; @@ -108,6 +108,7 @@ dse_possible_dead_store_p (gimple stmt, gimple *use_stmt) defvar = PHI_RESULT (temp); else defvar = gimple_vdef (temp); + defvar_def = temp; temp = NULL; FOR_EACH_IMM_USE_STMT (use_stmt, ui, defvar) { @@ -139,7 +140,14 @@ dse_possible_dead_store_p (gimple stmt, gimple *use_stmt) fail = true; BREAK_FROM_IMM_USE_STMT (ui); } - temp = use_stmt; + /* Do not consider the PHI as use if it dominates the + stmt defining the virtual operand we are processing, + we have processed it already in this case. */ + if (gimple_bb (defvar_def) != gimple_bb (use_stmt) + && !dominated_by_p (CDI_DOMINATORS, + gimple_bb (defvar_def), + gimple_bb (use_stmt))) + temp = use_stmt; } /* If the statement is a use the store is not dead. */ else if (ref_maybe_used_by_stmt_p (use_stmt, -- 2.7.4