diff options
| author | Erik Verbruggen <erik.verbruggen@digia.com> | 2014-05-13 13:05:25 +0200 |
|---|---|---|
| committer | The Qt Project <gerrit-noreply@qt-project.org> | 2014-06-06 14:50:20 +0200 |
| commit | f99ddc62ea468bff2700860e30d29be91d74473e (patch) | |
| tree | 13d20adfac92f501378073536e6f736faf7a5f1e /src/qml/compiler/qv4ssa.cpp | |
| parent | 0ee38bbecb0bd31683e5f73b3fec2a8129bf0894 (diff) | |
V4 IR: add def statements to the worklist when removing uses.
When removing a phi node, add the def statement for the (previously)
used temps to the worklist. These statements might now be eligible for
further optimizations (specifically removal when there are no uses
left).
Change-Id: I05d7c7bc0a243d328b5f9d1c2dcc53a10bd7491d
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
Diffstat (limited to 'src/qml/compiler/qv4ssa.cpp')
| -rw-r--r-- | src/qml/compiler/qv4ssa.cpp | 24 |
1 files changed, 11 insertions, 13 deletions
diff --git a/src/qml/compiler/qv4ssa.cpp b/src/qml/compiler/qv4ssa.cpp index 82a69b3224..9149c757b6 100644 --- a/src/qml/compiler/qv4ssa.cpp +++ b/src/qml/compiler/qv4ssa.cpp @@ -3107,8 +3107,10 @@ void purgeBB(BasicBlock *bb, IR::Function *func, DefUses &defUses, StatementWork if (!outStmt) continue; if (Phi *phi = outStmt->asPhi()) { - if (Temp *t = phi->d->incoming[idx]->asTemp()) + if (Temp *t = phi->d->incoming[idx]->asTemp()) { defUses.removeUse(phi, *t); + W += defUses.defStmt(*t); + } phi->d->incoming.remove(idx); W += phi; } else @@ -3215,6 +3217,13 @@ void optimizeSSA(StatementWorklist &W, DefUses &defUses, DominatorTree &df) Q_ASSERT(s); if (Phi *phi = s->asPhi()) { + // dead code elimination: + if (defUses.useCount(*phi->targetTemp) == 0) { + W += defUses.removeDefUses(phi); + W.remove(s); + continue; + } + // constant propagation: if (Const *c = isConstPhi(phi)) { replaceUses(phi->targetTemp, c, W); @@ -3233,23 +3242,12 @@ void optimizeSSA(StatementWorklist &W, DefUses &defUses, DominatorTree &df) if (Temp *t2 = e->asTemp()) { defUses.removeUse(s, *t2); defUses.addUses(*t2, newT2Uses); + W += defUses.defStmt(*t2); } defUses.removeDef(*t); W.remove(s); continue; } - - // dead code elimination: - if (defUses.useCount(*phi->targetTemp) == 0) { - foreach (Expr *in, phi->d->incoming) { - if (Temp *t = in->asTemp()) - W += defUses.defStmt(*t); - } - - defUses.removeDef(*phi->targetTemp); - W.remove(s); - continue; - } } else if (Move *m = s->asMove()) { if (Convert *convert = m->source->asConvert()) { if (Const *sourceConst = convert->expr->asConst()) { |