Support compound complex operations as l-values in C++. Add a test

case based on CodeGen/volatile-1.c which tests the current C++
semantics, and note the many, many places we fall short of them.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@119402 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 383 insertions, 0 deletions

diff --git a/test/CodeGenCXX/volatile-1.cpp b/test/CodeGenCXX/volatile-1.cpp
new file mode 100644
index 0000000000..4ff7e9e492
--- /dev/null
+++ b/test/CodeGenCXX/volatile-1.cpp
@@ -0,0 +1,383 @@
+// RUN: %clang_cc1 -Wno-unused-value -emit-llvm %s -o - | FileCheck %s
+
+// CHECK: @i = global [[INT:i[0-9]+]] 0
+volatile int i, j, k;
+volatile int ar[5];
+volatile char c;
+// CHECK: @ci = global [[CINT:%.*]] zeroinitializer
+volatile _Complex int ci;
+volatile struct S {
+#ifdef __cplusplus
+  void operator =(volatile struct S&o) volatile;
+#endif
+  int i;
+} a, b;
+
+//void operator =(volatile struct S&o1, volatile struct S&o2) volatile;
+int printf(const char *, ...);
+
+
+// CHECK: define void @{{.*}}test
+void test() {
+
+  asm("nop"); // CHECK: call void asm
+
+  // FIXME: should not load
+  i;
+  // CHECK-NEXT: volatile load [[INT]]* @i
+
+  (float)(ci);
+  // CHECK-NEXT: volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 0)
+  // CHECK-NEXT: volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // CHECK-NEXT: sitofp [[INT]]
+
+  // These are not uses in C++:
+  //   [expr.static.cast]p6:
+  //     The lvalue-to-rvalue . . . conversions are not applied to the expression.
+  (void)ci;
+  (void)a;
+
+  (void)(ci=ci);
+  // CHECK-NEXT: [[R:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 0)
+  // CHECK-NEXT: [[I:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // CHECK-NEXT: volatile store [[INT]] [[R]], [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 0)
+  // CHECK-NEXT: volatile store [[INT]] [[I]], [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+
+  (void)(i=j);
+  // CHECK-NEXT: [[T:%.*]] = volatile load [[INT]]* @j
+  // CHECK-NEXT: volatile store [[INT]] [[T]], [[INT]]* @i
+
+  // FIXME: extra load at end!
+  ci+=ci;
+  // CHECK-NEXT: [[R1:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 0)
+  // CHECK-NEXT: [[I1:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // CHECK-NEXT: [[R2:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 0)
+  // CHECK-NEXT: [[I2:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // Not sure why they're ordered this way.
+  // CHECK-NEXT: [[R:%.*]] = add [[INT]] [[R2]], [[R1]]
+  // CHECK-NEXT: [[I:%.*]] = add [[INT]] [[I2]], [[I1]]
+  // CHECK-NEXT: volatile store [[INT]] [[R]], [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 0)
+  // CHECK-NEXT: volatile store [[INT]] [[I]], [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // CHECK-NEXT: [[R1:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 0)
+  // CHECK-NEXT: [[I1:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+
+  // Note that C++ requires an extra volatile load over C from the LHS of the '+'.
+  (ci += ci) + ci;
+  // CHECK-NEXT: [[R1:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 0)
+  // CHECK-NEXT: [[I1:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // CHECK-NEXT: [[R2:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 0)
+  // CHECK-NEXT: [[I2:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // CHECK-NEXT: [[R:%.*]] = add [[INT]] [[R2]], [[R1]]
+  // CHECK-NEXT: [[I:%.*]] = add [[INT]] [[I2]], [[I1]]
+  // CHECK-NEXT: volatile store [[INT]] [[R]], [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 0)
+  // CHECK-NEXT: volatile store [[INT]] [[I]], [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // CHECK-NEXT: [[R1:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 0)
+  // CHECK-NEXT: [[I1:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // CHECK-NEXT: [[R2:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 0)
+  // CHECK-NEXT: [[I2:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // These additions can be elided.
+  // CHECK-NEXT: add [[INT]] [[R1]], [[R2]]
+  // CHECK-NEXT: add [[INT]] [[I1]], [[I2]]
+
+  asm("nop"); // CHECK-NEXT: call void asm
+
+  // Extra volatile load in C++.
+  (i += j) + k;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: add nsw [[INT]]
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: add nsw [[INT]]
+
+  asm("nop"); // CHECK-NEXT: call void asm
+
+  // Extra volatile load in C++.
+  (i += j) + 1;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: add nsw [[INT]]
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: add nsw [[INT]]
+
+  asm("nop"); // CHECK-NEXT: call void asm
+
+  ci+ci;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: add [[INT]]
+  // CHECK-NEXT: add [[INT]]
+
+  // FIXME: should not load
+  __real i;
+  // CHECK-NEXT: volatile load
+
+  +ci;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+
+  asm("nop"); // CHECK-NEXT: call void asm
+
+  (void)(i=i);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+
+  (float)(i=i);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: sitofp
+
+  (void)i;
+
+  i=i;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+
+  // Extra volatile load in C++.
+  i=i=i;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+
+  (void)__builtin_choose_expr(0, i=i, j=j);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+
+  // FIXME: shouldn't get these extra loads here, or the phi
+  k ? (i=i) : (j=j);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: icmp
+  // CHECK-NEXT: br i1
+  // CHECK: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: br label
+  // CHECK: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: br label
+  // CHECK: phi
+
+  (void)(i,(i=i));
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+
+  // FIXME: should not load k
+  i=i,k;
+  // CHECK-NEXT: volatile load [[INT]]* @i
+  // CHECK-NEXT: volatile store {{.*}}, [[INT]]* @i
+  // CHECK-NEXT: volatile load [[INT]]* @k
+
+  (i=j,k=j);
+  // CHECK-NEXT: volatile load [[INT]]* @j
+  // CHECK-NEXT: volatile store {{.*}}, [[INT]]* @i
+  // CHECK-NEXT: volatile load [[INT]]* @j
+  // CHECK-NEXT: volatile store {{.*}}, [[INT]]* @k
+
+  // FIXME: should not load 'k'
+  (i=j,k);
+  // CHECK-NEXT: volatile load [[INT]]* @j
+  // CHECK-NEXT: volatile store {{.*}}, [[INT]]* @i
+  // CHECK-NEXT: volatile load [[INT]]* @k
+
+  // FIXME: should not load either
+  (i,j);
+  // CHECK-NEXT: volatile load [[INT]]* @i
+  // CHECK-NEXT: volatile load [[INT]]* @j
+
+  // Extra load in C++.
+  i=c=k;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: trunc
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: sext
+  // CHECK-NEXT: volatile store
+
+  i+=k;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: add nsw [[INT]]
+  // CHECK-NEXT: volatile store
+
+  // FIXME: should not load!
+  ci;
+  // CHECK-NEXT: volatile load {{.*}} @ci, i32 0, i32 0
+  // CHECK-NEXT: volatile load {{.*}} @ci, i32 0, i32 1
+
+  asm("nop"); // CHECK-NEXT: call void asm
+
+  (int)ci;
+  // CHECK-NEXT: volatile load {{.*}} @ci, i32 0, i32 0
+  // CHECK-NEXT: volatile load {{.*}} @ci, i32 0, i32 1
+
+  (bool)ci;
+  // CHECK-NEXT: volatile load {{.*}} @ci, i32 0, i32 0
+  // CHECK-NEXT: volatile load {{.*}} @ci, i32 0, i32 1
+  // CHECK-NEXT: icmp ne
+  // CHECK-NEXT: icmp ne
+  // CHECK-NEXT: or i1
+
+  // FIXME: should not load!
+  ci=ci;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+
+  asm("nop"); // CHECK-NEXT: call void asm
+
+  // FIXME: should not load at end
+  // Extra load in C++.
+  ci=ci=ci;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+
+  __imag ci = __imag ci = __imag ci;
+  // CHECK-NEXT: [[T:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // CHECK-NEXT: volatile store [[INT]] [[T]], [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // CHECK-NEXT: [[T:%.*]] = volatile load [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+  // CHECK-NEXT: volatile store [[INT]] [[T]], [[INT]]* getelementptr inbounds ([[CINT]]* @ci, i32 0, i32 1)
+
+  __real (i = j);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+
+  __imag i;
+  // CHECK-NEXT: volatile load
+  
+  // ============================================================
+  // FIXME: Test cases we get wrong.
+
+  // A use.  We load all of a into a copy of a, then load i.  gcc forgets to do
+  // the assignment.
+  // (a = a).i;
+
+  // ============================================================
+  // Test cases where we intentionally differ from gcc, due to suspected bugs in
+  // gcc.
+
+  // Not a use.  gcc forgets to do the assignment.
+  // CHECK-NEXT: call
+  ((a=a),a);
+
+  // Not a use.  gcc gets this wrong, it doesn't emit the copy!  
+  // CHECK-NEXT: call
+  (void)(a=a);
+
+  // Not a use.  gcc got this wrong in 4.2 and omitted the side effects
+  // entirely, but it is fixed in 4.4.0.
+  __imag (i = j);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+
+  // C++ does an extra load here.  Note that we have to do full loads.
+  (float)(ci=ci);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: sitofp
+
+  // Not a use, bug?  gcc treats this as not a use, that's probably a
+  // bug due to tree folding ignoring volatile.
+  (int)(ci=ci);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+
+  // A use.
+  (float)(i=i);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: sitofp
+
+  // A use.  gcc treats this as not a use, that's probably a bug due to tree
+  // folding ignoring volatile.
+  (int)(i=i);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+
+  // A use.
+  -(i=j);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: sub
+
+  // A use.  gcc treats this a not a use, that's probably a bug due to tree
+  // folding ignoring volatile.
+  +(i=k);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+
+  // A use. gcc treats this a not a use, that's probably a bug due to tree
+  // folding ignoring volatile.
+  // FIXME: extra load at end
+  __real (ci=ci);
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+
+  // A use.
+  i + 0;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: add
+
+  // A use.
+  (i=j) + i;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: add
+
+  // A use.  gcc treats this as not a use, that's probably a bug due to tree
+  // folding ignoring volatile.
+  (i=j) + 0;
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: volatile store
+  // CHECK-NEXT: volatile load
+  // CHECK-NEXT: add
+
+  // FIXME: extra load of 'i'
+  (i,j)=k;
+  // CHECK-NEXT: volatile load [[INT]]* @k
+  // CHECK-NEXT: volatile load [[INT]]* @i
+  // CHECK-NEXT: volatile store {{.*}}, [[INT]]* @j
+
+  // FIXME: extra load of 'j'
+  (j=k,i)=i;
+  // CHECK-NEXT: volatile load [[INT]]* @i
+  // CHECK-NEXT: volatile load [[INT]]* @k
+  // CHECK-NEXT: volatile store {{.*}}, [[INT]]* @j
+  // CHECK-NEXT: volatile load [[INT]]* @j
+  // CHECK-NEXT: volatile store {{.*}}, [[INT]]* @i
+}