[compiler-rt] [flang] [llvm] [clang-tools-extra] [clang] [clang] Add support for new loop attribute [[clang::code_align()]] (PR #70762)

[via cfe-commits]

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@@ -0,0 +1,164 @@
+// RUN: %clang_cc1 -fsyntax-only -verify=expected,c-local -x c %s
+// RUN: %clang_cc1 -fsyntax-only -verify=expected,cpp-local -pedantic -x c++ -std=c++11 %s
+
+void foo() {
+  int i;
+  int a[10], b[10];
+
+  [[clang::code_align(8)]]
+  for (i = 0; i < 10; ++i) {  // this is OK
+    a[i] = b[i] = 0;
+  }
+  // expected-error at +1{{'code_align' attribute only applies to 'for', 'while', and 'do' statements}}
+  [[clang::code_align(4)]]
+  i = 7;
+  for (i = 0; i < 10; ++i) {
+    a[i] = b[i] = 0;
+  }
+
+  // expected-error at +1{{'code_align' attribute cannot be applied to a declaration}}
+  [[clang::code_align(12)]] int n[10];
+}
+
+void bar(int);
+// cpp-local-note at +1{{declared here}}
+void foo1(int A)
+{
+  // expected-error at +1{{'code_align' attribute requires an integer argument which is a constant power of two between 1 and 4096 inclusive; provided argument was 0}}
+  [[clang::code_align(0)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  // expected-error at +1{{'code_align' attribute requires an integer argument which is a constant power of two between 1 and 4096 inclusive; provided argument was -4}}
+  [[clang::code_align(-4)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+
+    // cpp-local-error at +2{{integral constant expression must have integral or unscoped enumeration type, not 'double'}}
+    // c-local-error at +1{{integer constant expression must have integer type, not 'double'}}
+  [[clang::code_align(64.0)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  // expected-error at +1{{'code_align' attribute takes one argument}}
+  [[clang::code_align()]]
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  // expected-error at +1{{'code_align' attribute takes one argument}}
+  [[clang::code_align(4,8)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  // no diagnostic is expected
+  [[clang::code_align(32)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  // cpp-local-error at +2{{integral constant expression must have integral or unscoped enumeration type, not 'const char[4]'}}
+  // c-local-error at +1{{integer constant expression must have integer type, not 'char[4]'}}
+  [[clang::code_align("abc")]]
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  [[clang::code_align(64)]] // OK
+  [[clang::code_align(64)]] // OK
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  [[clang::code_align(8)]]  // expected-note{{previous attribute is here}}
+  [[clang::code_align(64)]] // expected-error{{conflicting loop attribute 'code_align'}}
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  // expected-error at +1{{'code_align' attribute requires an integer argument which is a constant power of two between 1 and 4096 inclusive; provided argument was 7}}
+  [[clang::code_align(7)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  // expected-error at +1{{'code_align' attribute requires an integer argument which is a constant power of two between 1 and 4096 inclusive; provided argument was 5000}}
+  [[clang::code_align(5000)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  // expected-warning at +2{{integer literal is too large to be represented in a signed integer type, interpreting as unsigned}}
+  // expected-error at +1{{'code_align' attribute requires an integer argument which is a constant power of two between 1 and 4096 inclusive; provided argument was -9223372036854775808}}
+  [[clang::code_align(9223372036854775808)]]
+  for(int I=0; I<256; ++I) { bar(I); }
+
+  // expected-error at +1{{'code_align' attribute requires an integer argument which is a constant power of two between 1 and 4096 inclusive; provided argument was (__int128_t)1311768467294899680ULL << 64}}
+  [[clang::code_align((__int128_t)0x1234567890abcde0ULL << 64)]]
+  for(int I=0; I<256; ++I) { bar(I); }
+
+  // expected-error at +1 {{'code_align' attribute requires an integer argument which is a constant power of two between 1 and 4096 inclusive; provided argument was -922337203685477}}
+  [[clang::code_align(-922337203685477)]]
+  for(int I=0; I<256; ++I) { bar(I); }
+
+  // cpp-local-error at +3{{expression is not an integral constant expression}}
+  // cpp-local-note at +2{{left shift of negative value -1311768467294899680}}
+  // c-local-error at +1{{'code_align' attribute requires an integer argument which is a constant power of two between 1 and 4096 inclusive; provided argument was -(__int128_t)1311768467294899680ULL << 64}}
+  [[clang::code_align(-(__int128_t)0x1234567890abcde0ULL << 64)]]
+  for(int I=0; I<256; ++I) { bar(I); }
+
+  // cpp-local-error at +3{{expression is not an integral constant expression}}
+  // cpp-local-note at +2{{function parameter 'A' with unknown value cannot be used in a constant expression}}
+  // c-local-error at +1{{expression is not an integer constant expression}}
+  [[clang::code_align(A)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+}
+
+void check_code_align_expression() {
+  int a[10];
+
+  // Test that checks expression is not a constant expression.
+  int foo2; // cpp-local-note {{declared here}}
+  // c-local-error at +3{{expression is not an integer constant expression}}
+  // cpp-local-error at +2{{expression is not an integral constant expression}}
+  // cpp-local-note at +1{{read of non-const variable 'foo2' is not allowed in a constant expression}}
+  [[clang::code_align(foo2 + 1)]]
+  for (int i = 0; i != 10; ++i)
+    a[i] = 0;
+
+#if __cplusplus >= 201103L
+  // Test that checks expression is a constant expression.
+  constexpr int bars = 0;
+  [[clang::code_align(bars + 1)]]
+  for (int i = 0; i != 10; ++i)
+    a[i] = 0;
+#endif
+}
+
+#if __cplusplus >= 201103L
+template <int A, int B, int C, int D, int E>
+void code_align_dependent() {
+  [[clang::code_align(C)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  [[clang::code_align(A)]] // OK
+  [[clang::code_align(A)]] // OK
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  [[clang::code_align(A)]]
+  [[clang::code_align(E)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  // cpp-local-error at +1{{'code_align' attribute requires an integer argument which is a constant power of two between 1 and 4096 inclusive; provided argument was 23}}
+  [[clang::code_align(B)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+
+  // cpp-local-error at +2{{'code_align' attribute requires an integer argument which is a constant power of two between 1 and 4096 inclusive; provided argument was -10}}
+  // cpp-local-note@#neg-instantiation{{in instantiation of function template specialization}}
+  [[clang::code_align(D)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+}
+
+template<int ITMPL>
+void bar3() {
+  [[clang::code_align(8)]]
+  [[clang::code_align(ITMPL)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+}
+
+template<int ITMPL1>
+void bar4() {
+  [[clang::code_align(ITMPL1)]]
+  [[clang::code_align(32)]]
+  for(int I=0; I<128; ++I) { bar(I); }
+}
+
+int main() {
+  code_align_dependent<8, 23, 32, -10, 64>(); // #neg-instantiation
+  bar3 <4>();
----------------
smanna12 wrote:

@erichkeane, i have fixed this diagnostic issues with commit https://github.com/llvm/llvm-project/pull/70762/commits/6778154ef0d64052f62b75955a615d542bafb799

https://github.com/llvm/llvm-project/pull/70762