AMDGPU: Add support for 's' and 'v' asm constraints

Summary: 's' is used to specify sgprs and 'v' is used to specify vgprs.

Reviewers: arsenm, echristo

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D14307

llvm-svn: 253610

2 files changed, 23 insertions, 2 deletions

diff --git a/clang/lib/Basic/Targets.cpp b/clang/lib/Basic/Targets.cpp
index 648ef4b3d26..697a9f232e0 100644
--- a/clang/lib/Basic/Targets.cpp
+++ b/clang/lib/Basic/Targets.cpp
@@ -1826,8 +1826,15 @@ public:
   }
 
   bool validateAsmConstraint(const char *&Name,
-                             TargetInfo::ConstraintInfo &info) const override {
-    return true;
+                             TargetInfo::ConstraintInfo &Info) const override {
+    switch (*Name) {
+    default: break;
+    case 'v': // vgpr
+    case 's': // sgpr
+      Info.setAllowsRegister();
+      return true;
+    }
+    return false;
   }
 
   ArrayRef<Builtin::Info> getTargetBuiltins() const override {
diff --git a/clang/test/Sema/inline-asm-validate-amdgpu.cl b/clang/test/Sema/inline-asm-validate-amdgpu.cl
new file mode 100644
index 00000000000..d60b09e0ce9
--- /dev/null
+++ b/clang/test/Sema/inline-asm-validate-amdgpu.cl
@@ -0,0 +1,14 @@
+// REQUIRES: amdgpu-registered-target
+// RUN: %clang_cc1 -x cl -triple amdgcn -fsyntax-only  %s
+// expected-no-diagnostics
+
+kernel void test () {
+
+  int sgpr = 0, vgpr = 0, imm = 0;
+
+  // sgpr constraints
+  __asm__ ("s_mov_b32 %0, %1" : "=s" (sgpr) : "s" (imm) : );
+
+  // vgpr constraints
+  __asm__ ("v_mov_b32 %0, %1" : "=v" (vgpr) : "v" (imm) : );
+}