Avoid DXC warnings for missing bitwise op parantheses (#4004)

Resolves #3980

Based on the operator precedence, Slang may omits the parentheses if they
are not needed. DXC prints warnings for such cases and some applications
may treat the warnings as errors.

This commit emits parentheses to avoid the DXC warning even when they
are not needed.

1 files changed, 224 insertions, 0 deletions

diff --git a/tests/bugs/gh-3980.slang b/tests/bugs/gh-3980.slang
new file mode 100644
index 000000000..5e5e55d31
--- /dev/null
+++ b/tests/bugs/gh-3980.slang
@@ -0,0 +1,224 @@
+//TEST(compute):COMPARE_COMPUTE_EX(filecheck-buffer=BUF):-slang -compute -output-using-type
+//TEST(compute):COMPARE_COMPUTE_EX(filecheck-buffer=BUF):-slang -compute -output-using-type -dx12 -profile cs_6_6 -use-dxil
+//TEST(compute):COMPARE_COMPUTE_EX(filecheck-buffer=BUF):-vk -compute -shaderobj -output-using-type
+//TEST(compute):COMPARE_COMPUTE_EX(filecheck-buffer=BUF):-vk -compute -shaderobj -output-using-type -emit-spirv-directly
+//TEST(compute):COMPARE_COMPUTE_EX(filecheck-buffer=BUF):-cpu -compute -output-using-type
+//TEST(compute):COMPARE_COMPUTE_EX(filecheck-buffer=BUF):-cuda -compute -output-using-type
+
+// Slang removes parentheses characters for the bitwise operators when they are not needed.
+// DXC prints warning messages even when the expression is correct.
+// We are snoozing the warning and testing it here to prevent a regression.
+
+//TEST_INPUT: ubuffer(data=[0 1 2 3 4 5 6 7 8 9], stride=4):name inputBuffer
+RWStructuredBuffer<int> inputBuffer;
+
+//TEST_INPUT: ubuffer(data=[0 0 0 0], stride=4):out,name outputBuffer
+RWStructuredBuffer<int> outputBuffer;
+
+// -----------+----------+------------------------------+---------------
+// Precedence | Operator | Description                  | Associativity
+// -----------+----------+------------------------------+---------------
+// 4          | + -      | Addition and subtraction     | Left-to-right
+// -----------+----------+------------------------------+
+// 5          | << >>    | Bitwise left and right shift |
+// -----------+----------+------------------------------+
+// 8          | &        | Bitwise AND                  |
+// -----------+----------+------------------------------+
+// 9          | ^        | Bitwise XOR (exclusive or)   |
+// -----------+----------+------------------------------+
+// 10         | |        | Bitwise OR (inclusive or)    |
+// -----------+----------+------------------------------+---------------
+
+bool Test_And_Or()
+{
+    uint32_t a = inputBuffer[1];
+    uint32_t b = inputBuffer[3];
+    uint32_t c = inputBuffer[2];
+    uint32_t d = inputBuffer[6];
+
+    return true
+        && 3 == ((a & b) | (c & d))
+        && 0 == (a & (b | c) & d)
+        && 2 == (((a & b) | c) & d)
+        && 1 == (a & (b | (c & d)))
+        && 3 == (a & b | c & d)
+
+        && 2 == ((a | b) & (c | d))
+        && 7 == (a | (b & c) | d)
+        && 6 == (((a | b) & c) | d)
+        && 3 == (a | (b & (c | d)))
+        && 7 == (a | b & c | d)
+        ;
+}
+
+bool Test_And_Xor()
+{
+    uint32_t a = inputBuffer[1];
+    uint32_t b = inputBuffer[3];
+    uint32_t c = inputBuffer[2];
+    uint32_t d = inputBuffer[6];
+
+    return true
+        && 3 == ((a & b) ^ (c & d))
+        && 0 == (a & (b ^ c) & d)
+        && 2 == (((a & b) ^ c) & d)
+        && 1 == (a & (b ^ (c & d)))
+        && 3 == (a & b ^ c & d)
+
+        && 0 == ((a ^ b) & (c ^ d))
+        && 5 == (a ^ (b & c) ^ d)
+        && 4 == (((a ^ b) & c) ^ d)
+        && 1 == (a ^ (b & (c ^ d)))
+        && 5 == (a ^ b & c ^ d)
+        ;
+}
+
+bool Test_Xor_Or()
+{
+    uint32_t a = inputBuffer[1];
+    uint32_t b = inputBuffer[4];
+    uint32_t c = inputBuffer[2];
+    uint32_t d = inputBuffer[7];
+
+    return true
+        && 5 == ((a ^ b) | (c ^ d))
+        && 0 == (a ^ (b | c) ^ d)
+        && 0 == (((a ^ b) | c) ^ d)
+        && 4 == (a ^ (b | (c ^ d)))
+        && 5 == (a ^ b | c ^ d)
+
+        && 2 == ((a | b) ^ (c | d))
+        && 7 == (a | (b ^ c) | d)
+        && 7 == (((a | b) ^ c) | d)
+        && 3 == (a | (b ^ (c | d)))
+        && 7 == (a | b ^ c | d)
+        ;
+}
+
+bool Test_LShift_RShift()
+{
+    uint32_t a = inputBuffer[4];
+    uint32_t b = inputBuffer[1];
+    uint32_t c = inputBuffer[2];
+    uint32_t d = inputBuffer[3];
+
+    return true
+        && 0 == ((a << b) >> (c << d))
+        && 32 == (a << (b >> c) << d)
+        && 16 == (((a << b) >> c) << d)
+        && 4 == (a << (b >> (c << d)))
+        && 16 == (a << b >> c << d)
+
+        && 2 == ((a >> b) << (c >> d))
+        && 0 == (a >> (b << c) >> d)
+        && 1 == (((a >> b) << c) >> d)
+        && 2 == (a >> (b << (c >> d)))
+        && 1 == (a >> b << c >> d)
+        ;
+}
+
+bool Test_LShift_And()
+{
+    uint32_t a = inputBuffer[1];
+    uint32_t b = inputBuffer[5];
+    uint32_t c = inputBuffer[2];
+    uint32_t d = inputBuffer[4];
+
+    return true
+        && 32 == ((a << b) & (c << d))
+        && 16 == (a << (b & c) << d)
+        && 0 == (((a << b) & c) << d)
+        && 1 == (a << (b & (c << d)))
+        && 32 == (a << b & c << d)
+
+        && 1 == ((a & b) << (c & d))
+        && 0 == (a & (b << c) & d)
+        && 4 == (((a & b) << c) & d)
+        && 1 == (a & (b << (c & d)))
+        && 0 == (a & b << c & d)
+        ;
+}
+
+bool Test_LShift_Or()
+{
+    uint32_t a = inputBuffer[1];
+    uint32_t b = inputBuffer[2];
+    uint32_t c = inputBuffer[4];
+    uint32_t d = inputBuffer[3];
+
+    return true
+        && 36 == ((a << b) | (c << d))
+        && 512 == (a << (b | c) << d)
+        && 32 == (((a << b) | c) << d)
+        && 1073741824 == (a << ((b | (c << d)) - 4))
+        && 36 == (a << b | c << d)
+
+        && 384 == ((a | b) << (c | d))
+        && 35 == (a | (b << c) | d)
+        && 51 == (((a | b) << c) | d)
+        && 257 == (a | (b << (c | d)))
+        && 35 == (a | b << c | d)
+        ;
+}
+
+bool Test_LShift_Xor()
+{
+    uint32_t a = inputBuffer[1];
+    uint32_t b = inputBuffer[2];
+    uint32_t c = inputBuffer[4];
+    uint32_t d = inputBuffer[3];
+
+    return true
+        && 36 == ((a << b) ^ (c << d))
+        && 512 == (a << (b ^ c) << d)
+        && 0 == (((a << b) ^ c) << d)
+        && 1073741824 == ((a << ((b ^ (c << d)) - 4)))
+        && 36 == (a << b ^ c << d)
+
+        && 384 == ((a ^ b) << (c ^ d))
+        && 34 == (a ^ (b << c) ^ d)
+        && 51 == (((a ^ b) << c) ^ d)
+        && 257 == (a ^ (b << (c ^ d)))
+        && 34 == (a ^ b << c ^ d)
+        ;
+}
+
+bool Test_Add_LShift()
+{
+    uint32_t a = inputBuffer[1];
+    uint32_t b = inputBuffer[3];
+    uint32_t c = inputBuffer[2];
+    uint32_t d = inputBuffer[4];
+
+    return true
+        && 256 == ((a + b) << (c + d))
+        && 17 == (a + (b << c) + d)
+        && 20 == (((a + b) << c) + d)
+        && 193 == (a + (b << (c + d)))
+        && 256 == (a + b << c + d)
+
+        && 40 == ((a << b) + (c << d))
+        && 512 == (a << (b + c) << d)
+        && 160 == (((a << b) + c) << d)
+        && 1073741824 == (a << ((b + (c << d)) - 5))
+        && 512 == (a << b + c << d)
+        ;
+}
+
+[numthreads(1, 1, 1)]
+void computeMain(uint groupIndex : SV_GroupIndex, int3 dispatchThreadID: SV_DispatchThreadID)
+{
+    //BUF: 1
+    bool result = true
+        && Test_And_Or()
+        && Test_And_Xor()
+        && Test_Xor_Or()
+        && Test_LShift_RShift()
+        && Test_LShift_And()
+        && Test_LShift_Or()
+        && Test_LShift_Xor()
+        && Test_Add_LShift()
+        ;
+
+    outputBuffer[0] = int(result);
+}