From eb337d28c32b1b460cc85b3c00f8418ca535c77b Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Tue, 7 Mar 2023 11:04:55 +0100 Subject: [PATCH] tree-optimization/109046 - re-combine complex loads The following addresses PR109046 by adding an optimization to forwprop to combine a piecewise complex load to a complex load when there are no other uses of the components. That's something useful in general and easier to do than avoiding the splitting in complex lowering. The testcase exercises both the manual and the complex lowering case. PR tree-optimization/109046 * tree-ssa-forwprop.cc (pass_forwprop::execute): Combine piecewise complex loads. * gcc.dg/tree-ssa/forwprop-39.c: New testcase. --- gcc/testsuite/gcc.dg/tree-ssa/forwprop-39.c | 15 ++++++++++ gcc/tree-ssa-forwprop.cc | 33 ++++++++++++++++++++- 2 files changed, 47 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/forwprop-39.c diff --git a/gcc/testsuite/gcc.dg/tree-ssa/forwprop-39.c b/gcc/testsuite/gcc.dg/tree-ssa/forwprop-39.c new file mode 100644 index 000000000000..eb2930e77fd4 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/forwprop-39.c @@ -0,0 +1,15 @@ +/* { dg-do compile } */ +/* { dg-options "-std=c11 -O2 -fdump-tree-forwprop1 -fdump-tree-optimized" } */ + +#include + +extern void push1(void *p, float _Complex x); +void foo (void *q, float _Complex *x) +{ + float r = __real *x; + float i = __imag *x; + push1 (q, CMPLXF (r, i)); +} + +/* { dg-final { scan-tree-dump-not "COMPLEX_EXPR" "forwprop1" } } */ +/* { dg-final { scan-tree-dump-not "REALPART_EXPR" "optimized" } } */ diff --git a/gcc/tree-ssa-forwprop.cc b/gcc/tree-ssa-forwprop.cc index 03fe0a3f6dfb..e34f08889542 100644 --- a/gcc/tree-ssa-forwprop.cc +++ b/gcc/tree-ssa-forwprop.cc @@ -3669,7 +3669,8 @@ pass_forwprop::execute (function *fun) /* Rewrite stores of a single-use complex build expression to component-wise stores. */ use_operand_p use_p; - gimple *use_stmt; + gimple *use_stmt, *def1, *def2; + tree rhs2; if (single_imm_use (lhs, &use_p, &use_stmt) && gimple_store_p (use_stmt) && !gimple_has_volatile_ops (use_stmt) @@ -3703,6 +3704,36 @@ pass_forwprop::execute (function *fun) release_defs (stmt); gsi_remove (&gsi, true); } + /* Rewrite a component-wise load of a complex to a complex + load if the components are not used separately. */ + else if (TREE_CODE (rhs) == SSA_NAME + && has_single_use (rhs) + && ((rhs2 = gimple_assign_rhs2 (stmt)), true) + && TREE_CODE (rhs2) == SSA_NAME + && has_single_use (rhs2) + && (def1 = SSA_NAME_DEF_STMT (rhs), + gimple_assign_load_p (def1)) + && (def2 = SSA_NAME_DEF_STMT (rhs2), + gimple_assign_load_p (def2)) + && (gimple_vuse (def1) == gimple_vuse (def2)) + && !gimple_has_volatile_ops (def1) + && !gimple_has_volatile_ops (def2) + && gimple_assign_rhs_code (def1) == REALPART_EXPR + && gimple_assign_rhs_code (def2) == IMAGPART_EXPR + && operand_equal_p (TREE_OPERAND (gimple_assign_rhs1 + (def1), 0), + TREE_OPERAND (gimple_assign_rhs1 + (def2), 0))) + { + tree cl = TREE_OPERAND (gimple_assign_rhs1 (def1), 0); + gimple_assign_set_rhs_from_tree (&gsi, unshare_expr (cl)); + gcc_assert (gsi_stmt (gsi) == stmt); + gimple_set_vuse (stmt, gimple_vuse (def1)); + gimple_set_modified (stmt, true); + gimple_stmt_iterator gsi2 = gsi_for_stmt (def1); + gsi_remove (&gsi, false); + gsi_insert_after (&gsi2, stmt, GSI_SAME_STMT); + } else gsi_next (&gsi); } -- 2.47.2