Fix language server crash. (#7756)

* Fix language server crash.

* Fix tests.

* Fix.

* Revert changes.

1 files changed, 137 insertions, 0 deletions

diff --git a/tests/language-server/robustness-9.slang b/tests/language-server/robustness-9.slang
new file mode 100644
index 000000000..daf6b9edb
--- /dev/null
+++ b/tests/language-server/robustness-9.slang
@@ -0,0 +1,137 @@
+//TEST:LANG_SERVER(filecheck=CHECK):
+
+RWTexture2D<float4> texFrame; // Output texture
+uniform float iTime; 
+// In seconds
+uniform float2 iResolution; // Screen size
+
+static const float kInfinity = asfloat(0x7f800000);
+static const uint32_t kIdNone = 0xFFFFFFFF;
+
+struct Intersection
+{
+	float t = kInfinity;
+	uint32_t id = kIdNone;
+	
+	bool missed() {
+		return id == kIdNone;
+	}
+	
+	[mutating]
+	void update(uint32_t newId, float newT)
+	{
+		if(newT >= 0 && newT < t)
+		{
+			t = newT;
+			id = newId;
+		}
+	}
+};
+
+struct Ray
+{
+	float3 origin;
+	float3 direction;
+	float3 at(float t)
+	{
+		return mad(origin, direction, float3(t));
+	}
+};
+
+// Returns the t-value of the intersection of the infinite line
+// with the plane given by
+// `dot(planeNormal, p) == planeDist`.
+float intersectPlane(Ray ray, float3 planeNormal, float planeDist)
+{
+	// dot(planeNormal, o + d * t) == planeDist
+	// -> dot(planeNormal, o) + t * dot(planeNormal, d) == planeDist
+	// -> t = (planeDist - dot(planeNormal, o)) / dot(planeNormal, d)
+	return (planeDist - dot(planeNormal, ray.origin))
+		/ dot(planeNormal, ray.direction);
+}
+
+float2 sortLoHi(float2 v)
+{ 
+	
+
+struct OBB
+{
+	// Note that these are more parameters than we need;
+	// technically, the sides of an OBB must all be perpendicular,
+	// so there's only 3 (position) + 3 (side lengths) + 3 (rotation)
+	// degrees of freedom.
+	float3 corner;
+	float3 edges[3];
+	
+	// Returns the t-value of the intersection of the OBB with
+	// the ray.
+	// The returned t-value may be negative; i.e. this assumes
+	// the camera is outside of the box.
+	// On miss, returns infinity.
+	float intersect(Ray ray)
+	{
+		ray.origin -= corner;
+		
+		float2 tCloseFar;
+		float tFar;
+		[ForceUnroll]
+		for(int i = 0; i < 3; i++)
+		{
+			const float3 edge = edges[i];
+			const float edgeDist = dot(edge, ray.origin);
+			const float factor = rcp(dot(edge, ray.direction));
+			float2 slab = (float2(0, dot(edge, edge)) - edgeDist)
+				* factor;
+			slab = 
+			if(i == 0)
+			{
+				tClose = min(slab.x, slab.y);
+				tFar   = max(slab.x, slab.y);
+			}
+			else
+			{
+				tClose = min3(tClose, slab.x, slab.y);
+				tFar = max3(tFar, slab.x, slab.y);
+			}
+			thisSlab = sortLoHi(thisSlab);
+			tCloseFar.x = 
+		}
+		return kInfinity;
+	}
+};
+
+[shader("compute")]
+[numthreads(16, 16, 1)]
+void main(uint2 thread: SV_DispatchThreadID)
+{
+	float2 uv = (2.0 * float2(thread) - iResolution.xy) / iResolution.y;
+	
+	// Right-handed Z-up coordinate system, same as Blender's
+	Ray ray;
+	ray.origin = float3(0, -4, 4);
+	static const float kSqrtP5 = sqrt(.5);
+	ray.direction = float3(
+		uv.x,
+		kSqrtP5 -kSqrtP5 * uv.y,
+		-kSqrtP5 -kSqrtP5 * uv.y
+	);
+	
+	Intersection intersection;
+	intersection.update(0, intersectPlane(ray, float3(0,0,1), 0));
+	OBB obb = OBB(float3(-1,-1,-1),{float3(2,0,0),float3(0,2,0), float3(0,0,2)});
+	intersection.update(1, obb.intersect(ray));
+	
+	float3 color;
+	if(intersection.missed())
+	{
+		color = float3(0.0, 0.0, 1.0);
+	}
+	else
+	{
+		color = float3(intersection.t / 10.0);
+	}
+//COMPLETE:134,31
+	texFrame[thread] = float4(color, 1.0);
+}
+
+// CHECK: color