197448 2019-04-30 17:46:51 -0700 [WHLSL] Cannot assign through pointers 2019-05-31 09:12:13 -0700 1 1 1 Unclassified WebKit WebGPU WebKit Nightly Build Unspecified Unspecified RESOLVED DUPLICATE 198198 InRadar P1 Normal --- 195925 198399 1 mmaxfield saam justin_fan webkit-bug-importer oldest_to_newest 1531808 0 mmaxfield 2019-04-30 17:46:51 -0700 Consider the following WHLSL statement: *x = y; When we compile this, we naively turn this into auto temp1 = *x; temp1 = y; This doesn't actually assign through the pointer, instead it just reassigns a temporary The WHLSLFunctionWriter needs to be smart enough to understand how to emit code that assigns through a pointer. We also need to determine which situations it needs to be made smarter about. 1531815 1 mmaxfield 2019-04-30 17:58:28 -0700 It looks like after the property resolver runs, lvalues can only be either variable references or dereference expressions. Assigning to a variable reference will just work, so it looks like we only need to special case assigning to a dereference expression. Also, we shouldn't need to go digging through the AST; we can just handle the outermost dereference expression. 1531817 2 368638 mmaxfield 2019-04-30 18:08:54 -0700 Created attachment 368638 WIP 1535878 3 webkit-bug-importer 2019-05-13 17:07:32 -0700 <rdar://problem/50746281> 1535928 4 368638 mmaxfield 2019-05-13 19:30:47 -0700 Comment on attachment 368638 WIP View in context: https://bugs.webkit.org/attachment.cgi?id=368638&action=review > Source/WebCore/Modules/webgpu/WHLSL/Metal/WHLSLFunctionWriter.cpp:495 > + m_stack.append(rightName); This "if" block needs a return. 1538466 5 saam 2019-05-22 16:42:47 -0700 Myles is doing the WIP here in the property resolver patch. The only question we need to answer is if there are other areas where this matters? Maybe things to consider: *p++, etc These should probably be desugared though. Need to verify 1540647 6 mmaxfield 2019-05-30 22:53:30 -0700 This is needed for https://bugs.webkit.org/show_bug.cgi?id=198399. 1540648 7 mmaxfield 2019-05-30 22:54:17 -0700 void FunctionDefinitionWriter::visit(AST::DereferenceExpression& dereferenceExpression) { checkErrorAndVisit(dereferenceExpression.pointer()); auto right = m_stack.takeLast(); auto variableName = generateNextVariableName(); m_stringBuilder.append(makeString(AST::toString(*dereferenceExpression.typeAnnotation().leftAddressSpace()), ' ', m_typeNamer.mangledNameForType(dereferenceExpression.resolvedType()), "& ", variableName, " = *", right, ";\n")); m_stack.append(variableName); } 1540677 8 saam 2019-05-31 01:57:26 -0700 (In reply to Myles C. Maxfield from comment #6) > This is needed for https://bugs.webkit.org/show_bug.cgi?id=198399. Maybe you were running into the "&*x" problem? I also ran into this issue while trying to test the zero filling code. I took your change and turned it into a patch with a test here: https://bugs.webkit.org/show_bug.cgi?id=198198 1540730 9 mmaxfield 2019-05-31 09:12:13 -0700 *** This bug has been marked as a duplicate of bug 198198 *** 368638 2019-04-30 18:08:54 -0700 2019-05-30 22:58:22 -0700 WIP file.txt text/plain 1391 mmaxfield ZGlmZiAtLWdpdCBhL1NvdXJjZS9XZWJDb3JlL01vZHVsZXMvd2ViZ3B1L1dITFNML01ldGFsL1dI TFNMRnVuY3Rpb25Xcml0ZXIuY3BwIGIvU291cmNlL1dlYkNvcmUvTW9kdWxlcy93ZWJncHUvV0hM U0wvTWV0YWwvV0hMU0xGdW5jdGlvbldyaXRlci5jcHAKaW5kZXggMmZjMTQ2NTg2MTYuLjgzOTk3 MzQ5NjUxIDEwMDY0NAotLS0gYS9Tb3VyY2UvV2ViQ29yZS9Nb2R1bGVzL3dlYmdwdS9XSExTTC9N ZXRhbC9XSExTTEZ1bmN0aW9uV3JpdGVyLmNwcAorKysgYi9Tb3VyY2UvV2ViQ29yZS9Nb2R1bGVz L3dlYmdwdS9XSExTTC9NZXRhbC9XSExTTEZ1bmN0aW9uV3JpdGVyLmNwcApAQCAtNDg2LDEyICs0 ODYsMjAgQEAgdm9pZCBGdW5jdGlvbkRlZmluaXRpb25Xcml0ZXI6OnZpc2l0KEFTVDo6VmFyaWFi bGVEZWNsYXJhdGlvbiYgdmFyaWFibGVEZWNsYXJhdGkKIAogdm9pZCBGdW5jdGlvbkRlZmluaXRp b25Xcml0ZXI6OnZpc2l0KEFTVDo6QXNzaWdubWVudEV4cHJlc3Npb24mIGFzc2lnbm1lbnRFeHBy ZXNzaW9uKQogeworICAgIGlmIChpczxBU1Q6OkRlcmVmZXJlbmNlRXhwcmVzc2lvbj4oYXNzaWdu bWVudEV4cHJlc3Npb24ubGVmdCgpKSkgeworICAgICAgICBjaGVja0Vycm9yQW5kVmlzaXQoZG93 bmNhc3Q8QVNUOjpEZXJlZmVyZW5jZUV4cHJlc3Npb24+KGFzc2lnbm1lbnRFeHByZXNzaW9uLmxl ZnQoKSkucG9pbnRlcigpKTsKKyAgICAgICAgYXV0byBsZWZ0TmFtZSA9IG1fc3RhY2sudGFrZUxh c3QoKTsKKyAgICAgICAgY2hlY2tFcnJvckFuZFZpc2l0KGFzc2lnbm1lbnRFeHByZXNzaW9uLnJp Z2h0KCkpOworICAgICAgICBhdXRvIHJpZ2h0TmFtZSA9IG1fc3RhY2sudGFrZUxhc3QoKTsKKyAg ICAgICAgbV9zdHJpbmdCdWlsZGVyLmFwcGVuZChtYWtlU3RyaW5nKCcqJywgbGVmdE5hbWUsICIg PSAiLCByaWdodE5hbWUsICI7XG4iKSk7CisgICAgICAgIG1fc3RhY2suYXBwZW5kKHJpZ2h0TmFt ZSk7CisgICAgfQogICAgIGNoZWNrRXJyb3JBbmRWaXNpdChhc3NpZ25tZW50RXhwcmVzc2lvbi5s ZWZ0KCkpOwogICAgIGF1dG8gbGVmdE5hbWUgPSBtX3N0YWNrLnRha2VMYXN0KCk7CiAgICAgY2hl Y2tFcnJvckFuZFZpc2l0KGFzc2lnbm1lbnRFeHByZXNzaW9uLnJpZ2h0KCkpOwogICAgIGF1dG8g cmlnaHROYW1lID0gbV9zdGFjay50YWtlTGFzdCgpOwogICAgIG1fc3RyaW5nQnVpbGRlci5hcHBl bmQobWFrZVN0cmluZyhsZWZ0TmFtZSwgIiA9ICIsIHJpZ2h0TmFtZSwgIjtcbiIpKTsKLSAgICBt X3N0YWNrLmFwcGVuZChsZWZ0TmFtZSk7CisgICAgbV9zdGFjay5hcHBlbmQocmlnaHROYW1lKTsK IH0KIAogdm9pZCBGdW5jdGlvbkRlZmluaXRpb25Xcml0ZXI6OnZpc2l0KEFTVDo6Q2FsbEV4cHJl c3Npb24mIGNhbGxFeHByZXNzaW9uKQo=