Fix broken -emit-spirv-via-glsl test option (#7091)

Fixes issue #6898

The -emit-spirv-via-glsl slang-test option has been broken for
some amount of time. Tests that were using it were operating as
if using -emit-spirv-directly, leading to many duplicated tests.

After fixing the test option, there were an number of errors that
appeared as a result.

This change fixes the broken test option and the resulting test
errors. Some of the test errors revealed some legitimate issues,
such as:

-The GLSL bitCount instrinsic only supports 32-bit integers and
 requires emulation for other bit widths.
-Emitting GLSL 8-bit and 16-bit glsl integer types did not emit
 the proper extension requirements
-Emitting GLSL and casting for 16-bit integers was missing a
 closing parenthesis.
-Missing profile for GL_EXT_shader_explicit_arithmetic_types
-Missing toType cases for UInt8/Int8 for the kIROp_BitCast case
 in tryEmitInstExprImpl.

1 files changed, 118 insertions, 0 deletions

diff --git a/tests/glsl/integer_pack.slang b/tests/glsl/integer_pack.slang
new file mode 100644
index 000000000..cf2c49f9c
--- /dev/null
+++ b/tests/glsl/integer_pack.slang
@@ -0,0 +1,118 @@
+//TEST(compute, vulkan):COMPARE_COMPUTE(filecheck-buffer=BUF):-vk -compute -entry computeMain -allow-glsl
+//TEST(compute, vulkan):COMPARE_COMPUTE(filecheck-buffer=BUF):-vk -compute -entry computeMain -allow-glsl -emit-spirv-via-glsl
+
+#version 450
+
+//TEST_INPUT:ubuffer(data=[0xA802 0x1349 0xC2 0x91 0xB2 0x72], stride=4):out,name=inputBuffer
+layout(scalar) buffer MyBlock1
+{
+    uint32_t a;
+    uint32_t b;
+
+    uint32_t c;
+    uint32_t d;
+    uint32_t e;
+    uint32_t f;
+} inputBuffer;
+// BUF: A802
+// BUF-NEXT: 1349
+// BUF-NEXT: C2
+// BUF-NEXT: 91
+// BUF-NEXT: B2
+// BUF-NEXT: 72
+
+//TEST_INPUT:ubuffer(data=[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0], stride=4):out,name=outputBuffer
+layout(scalar) buffer MyBlock2
+{
+    uvec4 a;
+    ivec4 b;
+
+    uvec2 c;
+    ivec2 d;
+
+    uvec2 e;
+    ivec2 f;
+
+    uint32_t g;
+    int32_t h;
+
+    uint32_t i;
+    int32_t j;
+
+    uint32_t k;
+    int32_t l;
+
+    uint32_t m;
+    uint32_t n;
+} outputBuffer;
+
+layout(local_size_x = 1) in;
+void computeMain()
+{
+    uint32_t a = 0xF2845678;
+    outputBuffer.a = unpack8(a);
+    // BUF-NEXT: 78
+    // BUF-NEXT: 56
+    // BUF-NEXT: 84
+    // BUF-NEXT: F2
+
+    int32_t b = 0xF2845678;
+    outputBuffer.b = unpack8(b);
+    // BUF: 78
+    // BUF-NEXT: 56
+    // BUF-NEXT: FFFFFF84
+    // BUF-NEXT: FFFFFFF2
+
+    uint16_t c = 0xF256;
+    outputBuffer.c = unpack8(c);
+    // BUF-NEXT: 56
+    // BUF-NEXT: F2
+
+    int16_t d = 0xF256;
+    outputBuffer.d = unpack8(d);
+    // BUF-NEXT: 56
+    // BUF-NEXT: FFFFFFF2
+
+    uint32_t e = 0xF2845678;
+    outputBuffer.e = unpack16(e);
+    // BUF-NEXT: 5678
+    // BUF-NEXT: F284
+
+    int32_t f = 0xF2845678;
+    outputBuffer.f = unpack16(f);
+    // BUF-NEXT: 5678
+    // BUF-NEXT: FFFFF284
+
+    u16vec2 g = {0xF256, 0x1234};
+    outputBuffer.g = pack32(g);
+    // BUF-NEXT: 1234F256
+
+    i16vec2 h = {0xF256, 0x1234};
+    outputBuffer.h = pack32(h);
+    // BUF-NEXT: 1234F256
+
+    u8vec4 i = {0xF2, 0x56, 0x12, 0x34};
+    outputBuffer.i = pack32(i);
+    // BUF-NEXT: 341256F2
+
+    i8vec4 j = {0x82, 0x56, 0x12, 0x80};
+    outputBuffer.j = pack32(j);
+    // BUF-NEXT: 80125682
+
+    // Note: Below tests are mainly to verify that we don't emit invalid spirv code
+    u16vec2 k = {inputBuffer.a, inputBuffer.b};
+    outputBuffer.k = pack32(k);
+    // BUF-NEXT: 1349A802
+
+    i16vec2 l = {inputBuffer.a, inputBuffer.b};
+    outputBuffer.l = pack32(l);
+    // BUF-NEXT: 1349A802
+
+    u8vec4 m = {inputBuffer.c, inputBuffer.d, inputBuffer.e, inputBuffer.f};
+    outputBuffer.m = pack32(m);
+    // BUF-NEXT: 72B291C2
+
+    u8vec4 n = {inputBuffer.c, inputBuffer.d, inputBuffer.e, inputBuffer.f};
+    outputBuffer.n = pack32(n);
+    // BUF-NEXT: 72B291C2
+}