workaround for Intel OpCompositeConstruct bug

The SPIR-V spec permits constructing a vector from mixed vectors and
scalars, e.g. vec3(vec2, float). Intel's Vulkan driver does not handle
this correctly. We already have a workaround in place for vector
construction (writing the code as vec3(vec2.x, vec2.y, float) instead),
but missed that matrix construction can produce the same problem, as
each column requires a vector to be constructed for it. This CL extends
the workaround to handle matrix construction as well.

Bug: skia:7851
Change-Id: I0fe5d300ec7ad5db87bcc6662cf8371bcd6deed8
Reviewed-on: https://skia-review.googlesource.com/124321
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>

1 files changed, 11 insertions, 1 deletions

diff --git a/src/sksl/SkSLSPIRVCodeGenerator.cpp b/src/sksl/SkSLSPIRVCodeGenerator.cpp
index c5a5d2c303..e1488e8c2a 100644
--- a/src/sksl/SkSLSPIRVCodeGenerator.cpp
+++ b/src/sksl/SkSLSPIRVCodeGenerator.cpp
@@ -1247,7 +1247,17 @@ SpvId SPIRVCodeGenerator::writeMatrixConstructor(const Constructor& c, OutputStr
                 ASSERT(currentCount == 0);
                 columnIds.push_back(arguments[i]);
             } else {
-                currentColumn.push_back(arguments[i]);
+                if (c.fArguments[i]->fType.columns() == 1) {
+                    currentColumn.push_back(arguments[i]);
+                } else {
+                    SpvId componentType = this->getType(c.fArguments[i]->fType.componentType());
+                    for (int j = 0; j < c.fArguments[j]->fType.columns(); ++j) {
+                        SpvId swizzle = this->nextId();
+                        this->writeInstruction(SpvOpCompositeExtract, componentType, swizzle,
+                                               arguments[i], j, out);
+                        currentColumn.push_back(swizzle);
+                    }
+                }
                 currentCount += c.fArguments[i]->fType.columns();
                 if (currentCount == rows) {
                     currentCount = 0;