Fix SPIRV unsigned to signed widening casts (#7051)

* Fix unsigned to signed casts for SPIRV

* Add test

* Fix ICE crash

1 files changed, 35 insertions, 0 deletions

diff --git a/tests/spirv/int-cast-unsigned-to-signed.slang b/tests/spirv/int-cast-unsigned-to-signed.slang
new file mode 100644
index 000000000..0ec3203a4
--- /dev/null
+++ b/tests/spirv/int-cast-unsigned-to-signed.slang
@@ -0,0 +1,35 @@
+//TEST(compute):COMPARE_COMPUTE_EX(filecheck-buffer=BUF):-vk -compute -shaderobj  -output-using-type
+//TEST(compute):COMPARE_COMPUTE_EX(filecheck-buffer=BUF):-cpu -compute -shaderobj -output-using-type
+//TEST(compute):COMPARE_COMPUTE_EX(filecheck-buffer=BUF):-cuda -compute -shaderobj -output-using-type
+
+//TEST_INPUT:ubuffer(data=[0 0 0], stride=4):out,name outputBuffer
+RWStructuredBuffer<int> outputBuffer;
+
+//TEST_INPUT:ubuffer(data=[200], stride=4):name input1
+RWStructuredBuffer<uint8_t> input1;
+
+//TEST_INPUT:ubuffer(data=[35000], stride=4):name input2
+RWStructuredBuffer<uint16_t> input2;
+
+//TEST_INPUT:ubuffer(data=[201], stride=4):name input3
+RWStructuredBuffer<uint8_t> input3;
+
+//
+// Tests unsigned to signed casts to wider int.
+//
+
+[numthreads(1, 1, 1)]
+void computeMain(uint3 dispatchThreadID : SV_DispatchThreadID)
+{
+    uint index = dispatchThreadID.x;
+
+    // BUF: 200
+    outputBuffer[index] = input1[0];
+
+    // BUF: 35000
+    outputBuffer[index + 1] = input2[0];
+
+    // BUF: 201
+    int16_t a = input3[0];
+    outputBuffer[index + 2] = a;
+}