mewin/glslang
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Replace #422: Remove the redundant location setting in AST->SPIR-V.

Browse Source 
This was redundant in two ways:
1) it replicated algorithms owned in the front end, and
2) it sometimes left location information on both a block and its members.
This commit is contained in:
John Kessenich 2017-06-04 13:22:39 -06:00
parent 94c18a84cd
commit 7cdf3fc3c6
2 changed files with 7 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
SPIRV/GlslangToSpv.cpp
View File

@ -2407,7 +2407,6 @@ spv::Id TGlslangToSpvTraverser::convertGlslangStructToSpvType(const glslang::TTy
// Create a vector of struct types for SPIR-V to consume
std::vector<spv::Id> spvMembers;
int memberDelta = 0; // how much the member's index changes from glslang to SPIR-V, normally 0, except sometimes for blocks
int locationOffset = 0; // for use across struct members, when they are called recursively
for (int i = 0; i < (int)glslangMembers->size(); i++) {
glslang::TType& glslangMember = *(*glslangMembers)[i].type;
if (glslangMember.hiddenMember()) {
@ -2424,11 +2423,9 @@ spv::Id TGlslangToSpvTraverser::convertGlslangStructToSpvType(const glslang::TTy
glslang::TQualifier memberQualifier = glslangMember.getQualifier();
InheritQualifiers(memberQualifier, qualifier);
// manually inherit location; it's more complex
// manually inherit location
if (! memberQualifier.hasLocation() && qualifier.hasLocation())
memberQualifier.layoutLocation = qualifier.layoutLocation + locationOffset;
if (qualifier.hasLocation())
locationOffset += glslangIntermediate->computeTypeLocationSize(glslangMember);
memberQualifier.layoutLocation = qualifier.layoutLocation;
// recurse
spvMembers.push_back(convertGlslangToSpvType(glslangMember, explicitLayout, memberQualifier));
@ -2491,29 +2488,12 @@ void TGlslangToSpvTraverser::decorateStructType(const glslang::TType& type,
addMemberDecoration(spvType, member, memory[i]);
}
// Compute location decoration; tricky based on whether inheritance is at play and
// what kind of container we have, etc.
// TODO: This algorithm (and it's cousin above doing almost the same thing) should
// probably move to the linker stage of the front end proper, and just have the
// answer sitting already distributed throughout the individual member locations.
int location = -1; // will only decorate if present or inherited
// Location assignment was already completed correctly by the front end,
// just track whether a member needs to be decorated.
// Ignore member locations if the container is an array, as that's
// ill-specified and decisions have been made to not allow this anyway.
// The object itself must have a location, and that comes out from decorating the object,
// not the type (this code decorates types).
if (! type.isArray()) {
if (memberQualifier.hasLocation()) { // no inheritance, or override of inheritance
// struct members should not have explicit locations
assert(type.getBasicType() != glslang::EbtStruct);
location = memberQualifier.layoutLocation;
} else if (type.getBasicType() != glslang::EbtBlock) {
// If it is a not a Block, (...) Its members are assigned consecutive locations (...)
// The members, and their nested types, must not themselves have Location decorations.
} else if (qualifier.hasLocation()) // inheritance
location = qualifier.layoutLocation + locationOffset;
}
if (location >= 0)
builder.addMemberDecoration(spvType, member, spv::DecorationLocation, location);
// ill-specified and decisions have been made to not allow this.
if (! type.isArray() && memberQualifier.hasLocation())
builder.addMemberDecoration(spvType, member, spv::DecorationLocation, memberQualifier.layoutLocation);
if (qualifier.hasLocation()) // track for upcoming inheritance
locationOffset += glslangIntermediate->computeTypeLocationSize(glslangMember);

3
Test/baseResults/spv.450.tesc.out
View File

@ -38,11 +38,8 @@ Warning, version 450 is not yet complete; most version-specific features are pre
Decorate 11(TheBlock) Block
Decorate 16(tcBlock) Location 12
MemberDecorate 17(SingleBlock) 0 Patch
MemberDecorate 17(SingleBlock) 0 Location 2
MemberDecorate 17(SingleBlock) 1 Patch
MemberDecorate 17(SingleBlock) 1 Location 3
MemberDecorate 17(SingleBlock) 2 Patch
MemberDecorate 17(SingleBlock) 2 Location 4
Decorate 17(SingleBlock) Block
Decorate 19(singleBlock) Location 2
MemberDecorate 20(bn) 0 Patch