Append options for floating-point commutivity when related diagnostics are produced.
With this patch clang appends the command line options that would allow vectorization when floating-point commutativity is required. Specifically those are enabling fast-math or specifying a loop hint.
llvm-svn: 244492
diff --git a/clang/include/clang/Basic/DiagnosticFrontendKinds.td b/clang/include/clang/Basic/DiagnosticFrontendKinds.td
index 21058aa..080c738 100644
--- a/clang/include/clang/Basic/DiagnosticFrontendKinds.td
+++ b/clang/include/clang/Basic/DiagnosticFrontendKinds.td
@@ -45,6 +45,10 @@
InGroup<BackendOptimizationRemarkMissed>;
def remark_fe_backend_optimization_remark_analysis : Remark<"%0">, BackendInfo,
InGroup<BackendOptimizationRemarkAnalysis>;
+def remark_fe_backend_optimization_remark_analysis_fpcommute : Remark<"%0; "
+ "allow commutativity by specifying ‘#pragma clang loop vectorize(enable)’ "
+ "before the loop or by providing the compiler option ‘-ffast-math’">,
+ BackendInfo, InGroup<BackendOptimizationRemarkAnalysis>;
def warn_fe_backend_optimization_failure : Warning<"%0">, BackendInfo,
InGroup<BackendOptimizationFailure>, DefaultWarn;
def note_fe_backend_optimization_remark_invalid_loc : Note<"could "
diff --git a/clang/lib/CodeGen/CodeGenAction.cpp b/clang/lib/CodeGen/CodeGenAction.cpp
index d97a64e..d47997e 100644
--- a/clang/lib/CodeGen/CodeGenAction.cpp
+++ b/clang/lib/CodeGen/CodeGenAction.cpp
@@ -256,6 +256,8 @@
const llvm::DiagnosticInfoOptimizationRemarkMissed &D);
void OptimizationRemarkHandler(
const llvm::DiagnosticInfoOptimizationRemarkAnalysis &D);
+ void OptimizationRemarkHandler(
+ const llvm::DiagnosticInfoOptimizationRemarkAnalysisFPCommute &D);
void OptimizationFailureHandler(
const llvm::DiagnosticInfoOptimizationFailure &D);
};
@@ -500,6 +502,17 @@
D, diag::remark_fe_backend_optimization_remark_analysis);
}
+void BackendConsumer::OptimizationRemarkHandler(
+ const llvm::DiagnosticInfoOptimizationRemarkAnalysisFPCommute &D) {
+ // Optimization analysis remarks are active only if the -Rpass-analysis
+ // flag has a regular expression that matches the name of the pass
+ // name in \p D.
+ if (CodeGenOpts.OptimizationRemarkAnalysisPattern &&
+ CodeGenOpts.OptimizationRemarkAnalysisPattern->match(D.getPassName()))
+ EmitOptimizationMessage(
+ D, diag::remark_fe_backend_optimization_remark_analysis_fpcommute);
+}
+
void BackendConsumer::OptimizationFailureHandler(
const llvm::DiagnosticInfoOptimizationFailure &D) {
EmitOptimizationMessage(D, diag::warn_fe_backend_optimization_failure);
@@ -553,6 +566,12 @@
OptimizationRemarkHandler(
cast<DiagnosticInfoOptimizationRemarkAnalysis>(DI));
return;
+ case llvm::DK_OptimizationRemarkAnalysisFPCommute:
+ // Optimization remarks are always handled completely by this
+ // handler. There is no generic way of emitting them.
+ OptimizationRemarkHandler(
+ cast<DiagnosticInfoOptimizationRemarkAnalysisFPCommute>(DI));
+ return;
case llvm::DK_OptimizationFailure:
// Optimization failures are always handled completely by this
// handler.
diff --git a/clang/test/Frontend/optimization-remark-options.c b/clang/test/Frontend/optimization-remark-options.c
new file mode 100644
index 0000000..33cc9e0
--- /dev/null
+++ b/clang/test/Frontend/optimization-remark-options.c
@@ -0,0 +1,12 @@
+// RUN: %clang -O1 -fvectorize -Rpass-analysis=loop-vectorize -emit-llvm -S %s -o - 2>&1 | FileCheck %s
+
+// CHECK: {{.*}}:9:11: remark: loop not vectorized: vectorization requires changes in the order of operations, however IEEE 754 floating-point operations are not commutative; allow commutativity by specifying ‘#pragma clang loop vectorize(enable)’ before the loop or by providing the compiler option ‘-ffast-math’
+
+double foo(int N) {
+ double v = 0.0;
+
+ for (int i = 0; i < N; i++)
+ v = v + 1.0;
+
+ return v;
+}