https://github.com/shader-slang/slang
Tip revision: 662ef3ed90cd96435c05096c50f3486a1a6e9d18 authored by Yong He on 04 May 2023, 20:44:00 UTC
Update user-guide. (#2868)
Update user-guide. (#2868)
Tip revision: 662ef3e
addr-scope-fix.slang
//TEST(compute):COMPARE_COMPUTE_EX:-slang -compute -shaderobj -output-using-type
//TEST_INPUT:ubuffer(data=[0 0 0], stride=4):out,name=outputBuffer
RWStructuredBuffer<float> outputBuffer;
struct HitInfo
{
float val;
float getVal() { return val; }
}
struct PathInfo
{
HitInfo hit;
[mutating]
void setVal(float x)
{
hit.val = x;
}
}
void someOp(HitInfo hitInfo)
{
outputBuffer[0] = hitInfo.val;
}
void func(int x)
{
PathInfo path = {};
int i = 0;
if (x < 10)
{
// The `elementAddr(path, hit)` is first defined in this block.
// Note that this block dominates all remaining blocks in this
// function, so all future references to path.hit will use
// `elementAddr` inst defined here.
//
// The bug here is that when we emit code, the emit logic will
// find that the elementAddr inst is not in a valid region for
// future use and will try to create a local var for it. This will
// result a pointer typed var being created, and leads to invalid
// hlsl/glsl code.
//
// The fix is to hoist all always-fold insts to earliest point
// in the program instead of creating a var for it.
//
someOp(path.hit);
}
else
{
// This return makes the true block dominate the rest of the blocks
// from a region that does not "dominate" the rest code regions.
return;
}
while (i < 3)
{
if (i < 2)
{
path.setVal(1);
}
else
{
path.setVal(2);
}
// This is the point where we are using path.hit again.
outputBuffer[i] = path.hit.getVal();
i++;
}
}
[numthreads(1, 1, 1)]
void computeMain(uint3 dispatchThreadID: SV_DispatchThreadID)
{
func(4);
}