[OpenCL] Fix code generation of function-scope constant samplers.

Summary:
Constant samplers are handled as static variables and clang's code generation
library, which leads to llvm::unreachable. We bypass emitting sampler variable
as static since it's translated to a function call later.

Reviewers: yaxunl, Anastasia

Reviewed By: yaxunl, Anastasia

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D34342


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@318290 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 23 insertions, 26 deletions

diff --git a/lib/CodeGen/CGDecl.cpp b/lib/CodeGen/CGDecl.cpp
index 44a6db4750..e9f58cfac6 100644
--- a/lib/CodeGen/CGDecl.cpp
+++ b/lib/CodeGen/CGDecl.cpp
@@ -162,6 +162,10 @@ void CodeGenFunction::EmitVarDecl(const VarDecl &D) {
   // needs to be emitted like a static variable, e.g. a function-scope
   // variable in constant address space in OpenCL.
   if (D.getStorageDuration() != SD_Automatic) {
+    // Static sampler variables translated to function calls.
+    if (D.getType()->isSamplerT())
+      return;
+
     llvm::GlobalValue::LinkageTypes Linkage =
         CGM.getLLVMLinkageVarDefinition(&D, /*isConstant=*/false);
 
diff --git a/test/CodeGenOpenCL/sampler.cl b/test/CodeGenOpenCL/sampler.cl
index 3a7319cd78..22976c5766 100644
--- a/test/CodeGenOpenCL/sampler.cl
+++ b/test/CodeGenOpenCL/sampler.cl
@@ -20,6 +20,8 @@
 constant sampler_t glb_smp = CLK_ADDRESS_CLAMP_TO_EDGE | CLK_NORMALIZED_COORDS_TRUE | CLK_FILTER_LINEAR;
 // CHECK-NOT: glb_smp
 
+int get_sampler_initializer(void);
+
 void fnc4smp(sampler_t s) {}
 // CHECK: define spir_func void @fnc4smp(%opencl.sampler_t addrspace(2)* %
 
@@ -58,4 +60,20 @@ kernel void foo(sampler_t smp_par) {
   fnc4smp(5);
   // CHECK: [[SAMP:%[0-9]+]] = call %opencl.sampler_t addrspace(2)* @__translate_sampler_initializer(i32 5)
   // CHECK: call spir_func void @fnc4smp(%opencl.sampler_t addrspace(2)* [[SAMP]])
+
+  const sampler_t const_smp = CLK_ADDRESS_CLAMP_TO_EDGE | CLK_NORMALIZED_COORDS_TRUE | CLK_FILTER_LINEAR;
+  fnc4smp(const_smp);
+   // CHECK: [[CONST_SAMP:%[0-9]+]] = call %opencl.sampler_t addrspace(2)* @__translate_sampler_initializer(i32 35)
+  // CHECK: store %opencl.sampler_t addrspace(2)* [[CONST_SAMP]], %opencl.sampler_t addrspace(2)** [[CONST_SMP_PTR:%[a-zA-Z0-9]+]]
+  fnc4smp(const_smp);
+  // CHECK: [[SAMP:%[0-9]+]] = load %opencl.sampler_t addrspace(2)*, %opencl.sampler_t addrspace(2)** [[CONST_SMP_PTR]]
+  // CHECK: call spir_func void @fnc4smp(%opencl.sampler_t addrspace(2)* [[SAMP]])
+
+  constant sampler_t constant_smp = CLK_ADDRESS_CLAMP_TO_EDGE | CLK_NORMALIZED_COORDS_TRUE | CLK_FILTER_LINEAR;
+  fnc4smp(constant_smp);
+  // CHECK: [[SAMP:%[0-9]+]] = call %opencl.sampler_t addrspace(2)* @__translate_sampler_initializer(i32 35)
+  // CHECK: call spir_func void @fnc4smp(%opencl.sampler_t addrspace(2)* [[SAMP]])
+
+  // TODO: enable sampler initialization with non-constant integer.
+  //const sampler_t const_smp_func_init = get_sampler_initializer();
 }
diff --git a/test/SemaOpenCL/sampler_t.cl b/test/SemaOpenCL/sampler_t.cl
index 4d68dd20a1..5a1850b02c 100644
--- a/test/SemaOpenCL/sampler_t.cl
+++ b/test/SemaOpenCL/sampler_t.cl
@@ -46,36 +46,11 @@ const constant sampler_t glb_smp11 = CLK_ADDRESS_CLAMP_TO_EDGE | CLK_NORMALIZED_
 
 void kernel ker(sampler_t argsmp) {
   local sampler_t smp; // expected-error{{sampler type cannot be used with the __local and __global address space qualifiers}}
-  const sampler_t const_smp = CLK_ADDRESS_CLAMP_TO_EDGE | CLK_NORMALIZED_COORDS_TRUE | CLK_FILTER_LINEAR;
-  const sampler_t const_smp2;
-  const sampler_t const_smp3 = const_smp;
-  const sampler_t const_smp4 = f();
   const sampler_t const_smp5 = 1.0f; // expected-error{{initializing 'const sampler_t' with an expression of incompatible type 'float'}}
   const sampler_t const_smp6 = 0x100000000LL; // expected-error{{sampler_t initialization requires 32-bit integer, not 'long long'}}
 
-  foo(glb_smp);
-  foo(glb_smp2);
-  foo(glb_smp3);
-  foo(glb_smp4);
-  foo(glb_smp5);
-  foo(glb_smp6);
-  foo(glb_smp7);
-  foo(glb_smp8);
-  foo(glb_smp9);
-  foo(smp);
-  foo(sampler_str.smp);
-  foo(const_smp);
-  foo(const_smp2);
-  foo(const_smp3);
-  foo(const_smp4);
-  foo(const_smp5);
-  foo(const_smp6);
-  foo(argsmp);
-  foo(5);
   foo(5.0f); // expected-error {{passing 'float' to parameter of incompatible type 'sampler_t'}}
-  sampler_t sa[] = {argsmp, const_smp}; // expected-error {{array of 'sampler_t' type is invalid in OpenCL}}
-  foo(sa[0]);
-  foo(bad());
+  sampler_t sa[] = {argsmp, glb_smp}; // expected-error {{array of 'sampler_t' type is invalid in OpenCL}}
 }
 
 void bad(sampler_t*); // expected-error{{pointer to type 'sampler_t' is invalid in OpenCL}}