From 5196fe7c197a56548a4df99287e08ad3903927ff Mon Sep 17 00:00:00 2001
From: Artem Belevich <tra@google.com>
Date: Thu, 19 Mar 2015 18:40:25 +0000
Subject: [PATCH] Ignore device-side asm constraint errors while compiling CUDA
 code for host and vice versa.

Differential Revision: http://reviews.llvm.org/D8392

llvm-svn: 232747
---
 clang/lib/Sema/SemaStmtAsm.cpp                | 19 ++++++++++++++++---
 clang/test/SemaCUDA/asm-constraints-device.cu | 24 ++++++++++++++++++++++++
 clang/test/SemaCUDA/asm-constraints-mixed.cu  | 15 +++++++++++++++
 3 files changed, 55 insertions(+), 3 deletions(-)
 create mode 100644 clang/test/SemaCUDA/asm-constraints-device.cu
 create mode 100644 clang/test/SemaCUDA/asm-constraints-mixed.cu

diff --git a/clang/lib/Sema/SemaStmtAsm.cpp b/clang/lib/Sema/SemaStmtAsm.cpp
index c091cf8..179e207 100644
--- a/clang/lib/Sema/SemaStmtAsm.cpp
+++ b/clang/lib/Sema/SemaStmtAsm.cpp
@@ -124,6 +124,17 @@ StmtResult Sema::ActOnGCCAsmStmt(SourceLocation AsmLoc, bool IsSimple,
   // The parser verifies that there is a string literal here.
   assert(AsmString->isAscii());
 
+  bool ValidateConstraints = true;
+  if (getLangOpts().CUDA) {
+    // In CUDA mode don't verify asm constraints in device functions during host
+    // compilation and vice versa.
+    bool InDeviceMode = getLangOpts().CUDAIsDevice;
+    FunctionDecl *FD = getCurFunctionDecl();
+    bool IsDeviceFunction =
+        FD && (FD->hasAttr<CUDADeviceAttr>() || FD->hasAttr<CUDAGlobalAttr>());
+    ValidateConstraints = IsDeviceFunction == InDeviceMode;
+  }
+
   for (unsigned i = 0; i != NumOutputs; i++) {
     StringLiteral *Literal = Constraints[i];
     assert(Literal->isAscii());
@@ -133,7 +144,8 @@ StmtResult Sema::ActOnGCCAsmStmt(SourceLocation AsmLoc, bool IsSimple,
       OutputName = Names[i]->getName();
 
     TargetInfo::ConstraintInfo Info(Literal->getString(), OutputName);
-    if (!Context.getTargetInfo().validateOutputConstraint(Info))
+    if (ValidateConstraints &&
+        !Context.getTargetInfo().validateOutputConstraint(Info))
       return StmtError(Diag(Literal->getLocStart(),
                             diag::err_asm_invalid_output_constraint)
                        << Info.getConstraintStr());
@@ -207,8 +219,9 @@ StmtResult Sema::ActOnGCCAsmStmt(SourceLocation AsmLoc, bool IsSimple,
       InputName = Names[i]->getName();
 
     TargetInfo::ConstraintInfo Info(Literal->getString(), InputName);
-    if (!Context.getTargetInfo().validateInputConstraint(OutputConstraintInfos.data(),
-                                                NumOutputs, Info)) {
+    if (ValidateConstraints &&
+        !Context.getTargetInfo().validateInputConstraint(
+            OutputConstraintInfos.data(), NumOutputs, Info)) {
       return StmtError(Diag(Literal->getLocStart(),
                             diag::err_asm_invalid_input_constraint)
                        << Info.getConstraintStr());
diff --git a/clang/test/SemaCUDA/asm-constraints-device.cu b/clang/test/SemaCUDA/asm-constraints-device.cu
new file mode 100644
index 0000000..cdd2d32
--- /dev/null
+++ b/clang/test/SemaCUDA/asm-constraints-device.cu
@@ -0,0 +1,24 @@
+// Verify that we do check for constraints in device-side inline
+// assembly. Passing an illegal input/output constraint and look 
+// for corresponding error
+// RUN: %clang_cc1 -triple nvptx-unknown-cuda -fsyntax-only -fcuda-is-device -verify %s
+
+__attribute__((device)) void df() {
+  short h;
+  int a;
+  // asm with PTX constraints. Some of them are PTX-specific.
+  __asm__("output constraints"
+          : "=h"(h), // .u16 reg, OK
+            "=a"(a)  // expected-error {{invalid output constraint '=a' in asm}}
+          :          // None
+          );
+  __asm__("input constraints"
+          :           // None
+          : "f"(0.0), // .f32 reg, OK
+            "d"(0.0), // .f64 reg, OK
+            "h"(0),   // .u16 reg, OK
+            "r"(0),   // .u32 reg, OK
+            "l"(0),   // .u64 reg, OK
+            "a"(0)    // expected-error {{invalid input constraint 'a' in asm}}
+          );
+}
diff --git a/clang/test/SemaCUDA/asm-constraints-mixed.cu b/clang/test/SemaCUDA/asm-constraints-mixed.cu
new file mode 100644
index 0000000..a4ac9c6
--- /dev/null
+++ b/clang/test/SemaCUDA/asm-constraints-mixed.cu
@@ -0,0 +1,15 @@
+// RUN: %clang_cc1 -triple nvptx-unknown-cuda -fsyntax-only -fcuda-is-device -verify %s
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fsyntax-only -verify %s
+// expected-no-diagnostics
+
+__attribute__((device)) void df() {
+  short h;
+  // asm with PTX constraints. Some of them are PTX-specific.
+  __asm__("dont care" : "=h"(h): "f"(0.0), "d"(0.0), "h"(0), "r"(0), "l"(0));
+}
+
+void hf() {
+  int a;
+  // Asm with x86 constraints that are not supported by PTX.
+  __asm__("dont care" : "=a"(a): "a"(0), "b"(0), "c"(0));
+}
-- 
2.7.4