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| author | Chandler Carruth <chandlerc@gmail.com> | 2015-09-13 08:17:14 +0000 |
|---|---|---|
| committer | Chandler Carruth <chandlerc@gmail.com> | 2015-09-13 08:17:14 +0000 |
| commit | 8874b78697cf09fde54c95df6de43c1acd7e9b75 (patch) | |
| tree | 2c25dbe409b26697d6bc49d5f5766d8b3ce21bb1 /llvm/lib/Transforms | |
| parent | 8671fcbbd65f64947477b29fd0498523230eb1ee (diff) | |
| download | bcm5719-llvm-8874b78697cf09fde54c95df6de43c1acd7e9b75.tar.gz bcm5719-llvm-8874b78697cf09fde54c95df6de43c1acd7e9b75.zip | |
[FunctionAttrs] Factor the logic to test for a known non-null return out
of a method and into a re-usable static helper. We can potentially use
this function from the implementation of a new pass manager oriented
version of the pass. Also add some better documentation of exactly what
the semantic model of this routine is (it isn't trivial) and use a more
modern naming convention for it.
llvm-svn: 247524
Diffstat (limited to 'llvm/lib/Transforms')
| -rw-r--r-- | llvm/lib/Transforms/IPO/FunctionAttrs.cpp | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/llvm/lib/Transforms/IPO/FunctionAttrs.cpp b/llvm/lib/Transforms/IPO/FunctionAttrs.cpp index 3ea54687365..cfeedf6d1db 100644 --- a/llvm/lib/Transforms/IPO/FunctionAttrs.cpp +++ b/llvm/lib/Transforms/IPO/FunctionAttrs.cpp @@ -74,8 +74,6 @@ private: bool AddArgumentAttrs(const CallGraphSCC &SCC); bool IsFunctionMallocLike(Function *F, SmallPtrSet<Function *, 8> &) const; bool AddNoAliasAttrs(const CallGraphSCC &SCC); - bool ReturnsNonNull(Function *F, SmallPtrSet<Function *, 8> &, - bool &Speculative) const; bool AddNonNullAttrs(const CallGraphSCC &SCC); bool annotateLibraryCalls(const CallGraphSCC &SCC); }; @@ -798,9 +796,14 @@ bool FunctionAttrs::AddNoAliasAttrs(const CallGraphSCC &SCC) { } /// Tests whether this function is known to not return null. -bool FunctionAttrs::ReturnsNonNull(Function *F, - SmallPtrSet<Function *, 8> &SCCNodes, - bool &Speculative) const { +/// +/// Requires that the function returns a pointer. +/// +/// Returns true if it believes the function will not return a null, and sets +/// \p Speculative based on whether the returned conclusion is a speculative +/// conclusion due to SCC calls. +static bool isReturnNonNull(Function *F, SmallPtrSet<Function *, 8> &SCCNodes, + const TargetLibraryInfo &TLI, bool &Speculative) { assert(F->getReturnType()->isPointerTy() && "nonnull only meaningful on pointer types"); Speculative = false; @@ -814,7 +817,7 @@ bool FunctionAttrs::ReturnsNonNull(Function *F, Value *RetVal = FlowsToReturn[i]; // If this value is locally known to be non-null, we're good - if (isKnownNonNull(RetVal, TLI)) + if (isKnownNonNull(RetVal, &TLI)) continue; // Otherwise, we need to look upwards since we can't make any local @@ -902,7 +905,7 @@ bool FunctionAttrs::AddNonNullAttrs(const CallGraphSCC &SCC) { continue; bool Speculative = false; - if (ReturnsNonNull(F, SCCNodes, Speculative)) { + if (isReturnNonNull(F, SCCNodes, *TLI, Speculative)) { if (!Speculative) { // Mark the function eagerly since we may discover a function // which prevents us from speculating about the entire SCC |
