[cfe-commits] r169054 - in /cfe/trunk: include/clang/Basic/DiagnosticSemaKinds.td lib/Basic/Targets.cpp test/CodeGen/arm-asm-warn.c

[Bill Wendling]

Author: void
Date: Fri Nov 30 17:18:12 2012
New Revision: 169054

URL: http://llvm.org/viewvc/llvm-project?rev=169054&view=rev
Log:
Don't warn if the input size is less than the register size. Also don't warn if
the output size is greater than the register size. No truncation occurs with
those. Reword warning to make it clearer what's the problem is.

Modified:
    cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
    cfe/trunk/lib/Basic/Targets.cpp
    cfe/trunk/test/CodeGen/arm-asm-warn.c

Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=169054&r1=169053&r2=169054&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original)
+++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Fri Nov 30 17:18:12 2012
@@ -5152,7 +5152,8 @@
     "accepted due to -fheinous-gnu-extensions, but clang may remove support "
     "for this in the future">;
   def warn_asm_mismatched_size_modifier : Warning<
-    "the size being stored is truncated, use a modifier to specify the size">,
+    "the value is truncated when put into register, "
+    "use a modifier to specify the size">,
     InGroup<ASMOperandWidths>;
 }
 

Modified: cfe/trunk/lib/Basic/Targets.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Basic/Targets.cpp?rev=169054&r1=169053&r2=169054&view=diff
==============================================================================
--- cfe/trunk/lib/Basic/Targets.cpp (original)
+++ cfe/trunk/lib/Basic/Targets.cpp Fri Nov 30 17:18:12 2012
@@ -3364,6 +3364,8 @@
   virtual bool validateConstraintModifier(StringRef Constraint,
                                           const char Modifier,
                                           unsigned Size) const {
+    bool isOutput = (Constraint[0] == '=');
+
     // Strip off constraint modifiers.
     while (Constraint[0] == '=' ||
            Constraint[0] == '+' ||
@@ -3375,7 +3377,7 @@
     case 'r': {
       switch (Modifier) {
       default:
-        return Size == 32;
+        return (isOutput && Size >= 32) || Size <= 32;
       case 'q':
         // A register of size 32 cannot fit a vector type.
         return false;

Modified: cfe/trunk/test/CodeGen/arm-asm-warn.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/arm-asm-warn.c?rev=169054&r1=169053&r2=169054&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/arm-asm-warn.c (original)
+++ cfe/trunk/test/CodeGen/arm-asm-warn.c Fri Nov 30 17:18:12 2012
@@ -1,7 +1,16 @@
 // REQUIRES: arm-registered-target
 // RUN: %clang_cc1 -triple armv7 %s -emit-llvm -o /dev/null
-// <rdar://problem/12284092>
 
+char bar();
+
+void t1(int x, char y) {
+  __asm__ volatile("mcr p15, 0, %1, c9, c12, 5;"
+                   "mrc p15, 0, %0, c9, c13, 2;"
+                   : "=r" (x)
+                   : "r" (bar())); // no warning
+}
+
+// <rdar://problem/12284092>
 typedef __attribute__((neon_vector_type(2))) long long int64x2_t;
 typedef struct int64x2x4_t {
   int64x2_t val[4];
@@ -9,10 +18,10 @@
 int64x2x4_t t2(const long long a[]) {
   int64x2x4_t r;
   __asm__("vldm %[a], { %q[r0], %q[r1], %q[r2], %q[r3] }"
-          : [r0] "=r"(r.val[0]), // expected-warning {{the size being stored is truncated, use a modifier to specify the size}}
-            [r1] "=r"(r.val[1]), // expected-warning {{the size being stored is truncated, use a modifier to specify the size}}
-            [r2] "=r"(r.val[2]), // expected-warning {{the size being stored is truncated, use a modifier to specify the size}}
-            [r3] "=r"(r.val[3])  // expected-warning {{the size being stored is truncated, use a modifier to specify the size}}
+          : [r0] "=r"(r.val[0]), // expected-warning {{the value is truncated when put into register, use a modifier to specify the size}}
+            [r1] "=r"(r.val[1]), // expected-warning {{the value is truncated when put into register, use a modifier to specify the size}}
+            [r2] "=r"(r.val[2]), // expected-warning {{the value is truncated when put into register, use a modifier to specify the size}}
+            [r3] "=r"(r.val[3])  // expected-warning {{the value is truncated when put into register, use a modifier to specify the size}}
           : [a] "r"(a));
   return r;
 }