tint/hlsl: remove [loop] attribute on all loops
I added the forcing of the "loop" attribute to all loops to address FXC
failing on uniformity errors related to gradients in loops. Since then,
Tint now implements UA and it recently became an error, so we no longer
need this hack. As a result, FXC is now better able to cope with loops
that it determines executes 0 times.
Most e2e tests are affected because so many use loops, but 27 tests that
were previously failing are now passing with this change:
tint/bug/tint/1538.wgsl.expected.fxc.hlsl
tint/bug/tint/1604.wgsl.expected.fxc.hlsl
tint/bug/tint/1605.wgsl.expected.fxc.hlsl
tint/unittest/reader/spirv/SpvParserCFGTest_ClassifyCFGEdges_LoopBreak_FromLoopHeader_SingleBlockLoop_TrueBranch.spvasm.expected.fxc.hlsl
tint/unittest/reader/spirv/SpvParserCFGTest_ComputeBlockOrder_Loop_HeaderHasBreakUnless.spvasm.expected.fxc.hlsl
tint/unittest/reader/spirv/SpvParserCFGTest_EmitBody_IfSelection_TrueBranch_LoopBreak.spvasm.expected.fxc.hlsl
tint/unittest/reader/spirv/SpvParserCFGTest_FindIfSelectionInternalHeaders_TrueBranch_LoopBreak_Ok.spvasm.expected.fxc.hlsl
tint/unittest/reader/spirv/SpvParserFunctionVarTest_EmitStatement_Phi_MultiBlockLoopIndex.spvasm.expected.fxc.hlsl
tint/unittest/reader/spirv/SpvParserFunctionVarTest_EmitStatement_Phi_SingleBlockLoopIndex.spvasm.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/cov-dead-code-unreachable-merge/0-opt.spvasm.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/cov-dead-code-unreachable-merge/0-opt.wgsl.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/similar-nested-ifs/0-opt.spvasm.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/similar-nested-ifs/0-opt.wgsl.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/spv-load-from-frag-color/1.spvasm.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/spv-load-from-frag-color/1.wgsl.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/stable-binarysearch-tree-false-if-discard-loop/0.spvasm.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/stable-binarysearch-tree-false-if-discard-loop/0.wgsl.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/stable-binarysearch-tree-fragcoord-less-than-zero/0.spvasm.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/stable-binarysearch-tree-fragcoord-less-than-zero/0.wgsl.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/stable-binarysearch-tree-fragcoord-less-than-zero/1.spvasm.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/stable-binarysearch-tree-fragcoord-less-than-zero/1.wgsl.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/stable-binarysearch-tree-with-loop-read-write-global/0-opt.spvasm.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/stable-binarysearch-tree-with-loop-read-write-global/0-opt.wgsl.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/stable-binarysearch-tree-with-loop-read-write-global/1.spvasm.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/stable-binarysearch-tree-with-loop-read-write-global/1.wgsl.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/write-red-after-search/0-opt.spvasm.expected.fxc.hlsl
tint/vk-gl-cts/graphicsfuzz/write-red-after-search/0-opt.wgsl.expected.fxc.hlsl
Bug: tint:1522
Bug: tint:1538
Bug: tint:1604
Bug: tint:1605
Change-Id: I530b846b6b8df122ab351ff7b85d3e1c9ac11526
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/104121
Reviewed-by: Ben Clayton <bclayton@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
diff --git a/src/tint/writer/hlsl/generator_impl.cc b/src/tint/writer/hlsl/generator_impl.cc
index 48090d3..3edb560 100644
--- a/src/tint/writer/hlsl/generator_impl.cc
+++ b/src/tint/writer/hlsl/generator_impl.cc
@@ -143,13 +143,6 @@
return s;
}
-const char* LoopAttribute() {
- // Force loops not to be unrolled to work around FXC compilation issues when
- // it attempts and fails to unroll loops when it contains gradient operations.
- // https://docs.microsoft.com/en-us/windows/win32/direct3dhlsl/dx-graphics-hlsl-while
- return "[loop] ";
-}
-
} // namespace
SanitizedResult::SanitizedResult() = default;
@@ -3365,7 +3358,7 @@
};
TINT_SCOPED_ASSIGNMENT(emit_continuing_, emit_continuing);
- line() << LoopAttribute() << "while (true) {";
+ line() << "while (true) {";
{
ScopedIndent si(this);
if (!EmitStatements(stmt->body->statements)) {
@@ -3435,7 +3428,7 @@
};
TINT_SCOPED_ASSIGNMENT(emit_continuing_, emit_continuing);
- line() << LoopAttribute() << "while (true) {";
+ line() << "while (true) {";
increment_indent();
TINT_DEFER({
decrement_indent();
@@ -3458,7 +3451,7 @@
// For-loop can be generated.
{
auto out = line();
- out << LoopAttribute() << "for";
+ out << "for";
{
ScopedParen sp(out);
@@ -3507,7 +3500,7 @@
// as a regular while in HLSL. Instead we need to generate a `while(true)` loop.
bool emit_as_loop = cond_pre.lines.size() > 0;
if (emit_as_loop) {
- line() << LoopAttribute() << "while (true) {";
+ line() << "while (true) {";
increment_indent();
TINT_DEFER({
decrement_indent();
@@ -3523,7 +3516,7 @@
// While can be generated.
{
auto out = line();
- out << LoopAttribute() << "while";
+ out << "while";
{
ScopedParen sp(out);
out << cond_buf.str();