Changes:
a70113c Fix metal issue (#6361)
7435d5d Don't remove in-use globals (#6359)
944c19b (origin/master, origin/HEAD, master) Add support for GLSL interface blocks (#6351)
4c8edd7 Add CMake build target vs2019-dev that enables IR break (#6354)
adde262 Fix modifier parsing. (#6347)
1ea2ab1 Disallow only resources in constant buffers in parameterblocks on metal (#6342)
ccc75cd Reflection Fixes. (#6346)
8406b56 Migrate slang-test away from deprecated Slang API (#6343)
74852ce Allow LHS of where to be any type. (#6333)
3f102af Fix crash when handling uninitialized resource type (#6338)
0fee8c1 build core and glsl modules in the same slang-bootstrap invocation (#6341)
ee99bec Correct dependencies on core module source (#6340)
6f42676 Correct location of copy-headers target (#6327)
96529df Update build-llvm.ps1 (#6336)
551bbb5 Add checking for differentiability of the primal substitute function. (#6277)
0b4e463 Add raypayload decoration to ray payload structs (#6164)
0bc18d2 Emit missing atomic64 capability, fix int-typed builtin used in both vs and fs. (#6314)
3c2d46a Remove the docs/proposals directory (#6313)
133bd25 Add support for Metal subgroup/simd operations (#6247)
f761ab0 Fix compilation on musl libc targets (#6334)
94c4582 Add WGSL to list of formats supporting multiple entry points (#6324)
67dfc9b Propagate the MemoryQualifierSetDecoration (#6315)
57b09a8 Use and() and or() functions for logical-AND and OR (#6310)