With the newly simplified SourceMgr interfaces and the generalized

SrcMgrDiagHandler, we can improve clang diagnostics for inline asm:
instead of reporting them on a source line of the original line,
we can report it on the correct line wherever the string literal came
from. For something like this:

void foo() {
  asm("push %rax\n"
      ".code32\n");
}

we used to get this: (note that the line in t.c isn't helpful)

t.c:4:7: error: warning: ignoring directive for now
  asm("push %rax\n"
      ^
<inline asm>:2:1: note: instantiated into assembly here
.code32
^

now we get:

t.c:5:8: error: warning: ignoring directive for now
      ".code32\n"
       ^
<inline asm>:2:1: note: instantiated into assembly here
.code32
^

Note that we're pointing to line 5 properly now.

llvm-svn: 119488
This commit is contained in:
Chris Lattner 2010-11-17 08:20:42 +00:00
parent 068f2ab10f
commit 79ffdc7581
2 changed files with 15 additions and 6 deletions

View File

@ -2625,8 +2625,8 @@ call void asm alignstack "eieio", ""()
<div class="doc_text">
<p>The call instructions that wrap inline asm nodes may have a "!srcloc" MDNode
attached to it that contains a constant integer. If present, the code
generator will use the integer as the location cookie value when report
attached to it that contains a list of constant integers. If present, the
code generator will use the integer as the location cookie value when report
errors through the LLVMContext error reporting mechanisms. This allows a
front-end to correlate backend errors that occur with inline asm back to the
source code that produced it. For example:</p>
@ -2638,7 +2638,8 @@ call void asm sideeffect "something bad", ""()<b>, !srcloc !42</b>
</pre>
<p>It is up to the front-end to make sense of the magic numbers it places in the
IR.</p>
IR. If the MDNode contains multiple constants, the code generator will use
the one that corresponds to the line of the asm that the error occurs on.</p>
</div>

View File

@ -49,11 +49,19 @@ static void SrcMgrDiagHandler(const SMDiagnostic &Diag, void *diagInfo) {
SrcMgrDiagInfo *DiagInfo = static_cast<SrcMgrDiagInfo *>(diagInfo);
assert(DiagInfo && "Diagnostic context not passed down?");
// If the inline asm had metadata associated with it, pull out a location
// cookie corresponding to which line the error occurred on.
unsigned LocCookie = 0;
if (const MDNode *LocInfo = DiagInfo->LocInfo)
if (LocInfo->getNumOperands() > 0)
if (const ConstantInt *CI = dyn_cast<ConstantInt>(LocInfo->getOperand(0)))
if (const MDNode *LocInfo = DiagInfo->LocInfo) {
unsigned ErrorLine = Diag.getLineNo()-1;
if (ErrorLine >= LocInfo->getNumOperands())
ErrorLine = 0;
if (LocInfo->getNumOperands() != 0)
if (const ConstantInt *CI =
dyn_cast<ConstantInt>(LocInfo->getOperand(ErrorLine)))
LocCookie = CI->getZExtValue();
}
DiagInfo->DiagHandler(Diag, DiagInfo->DiagContext, LocCookie);
}