writer/hlsl: Special case negative zero

Fixed: tint:960
Change-Id: I04de8713fe299607f32fd93288a22b75a9dff381
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/58760
Reviewed-by: Ben Clayton <bclayton@chromium.org>
Reviewed-by: James Price <jrprice@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
This commit is contained in:
Ben Clayton
2021-07-20 12:45:30 +00:00
committed by Tint LUCI CQ
parent c6a73298c4
commit efceb83536
11 changed files with 147 additions and 7 deletions

View File

@@ -2502,13 +2502,20 @@ bool GeneratorImpl::EmitLiteral(std::ostream& out, ast::Literal* lit) {
if (auto* l = lit->As<ast::BoolLiteral>()) {
out << (l->IsTrue() ? "true" : "false");
} else if (auto* fl = lit->As<ast::FloatLiteral>()) {
if (std::isinf(fl->value())) {
out << (fl->value() >= 0 ? "asfloat(0x7f800000u)"
: "asfloat(0xff800000u)");
} else if (std::isnan(fl->value())) {
out << "asfloat(0x7fc00000u)";
} else {
out << FloatToString(fl->value()) << "f";
bool positive = !std::signbit(fl->value());
switch (std::fpclassify(fl->value())) {
case FP_INFINITE:
out << (positive ? "asfloat(0x7f800000u)" : "asfloat(0xff800000u)");
break;
case FP_NAN:
out << "asfloat(0x7fc00000u)";
break;
case FP_ZERO:
out << (positive ? "0.0f" : "asfloat(0x80000000u)");
break;
default:
out << FloatToString(fl->value()) << "f";
break;
}
} else if (auto* sl = lit->As<ast::SintLiteral>()) {
out << sl->value();