Fixed the lost FastMathFlags for CALL operations in SLPVectorizer.

Vyacheslav Klochkov · Vyacheslav Klochkov · commit b3dc774a9963 · 2016-11-16T00:55:50.000Z
Reviewer: Michael Zolotukhin. Differential Revision: https://reviews.llvm.org/D26575 llvm-svn: 287064
diff --git a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -2641,6 +2641,7 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
         ExternalUses.push_back(ExternalUser(ScalarArg, cast<User>(V), 0));
 
       E->VectorizedValue = V;
+      propagateIRFlags(E->VectorizedValue, E->Scalars);
       ++NumVectorInstructions;
       return V;
     }
diff --git a/llvm/test/Transforms/SLPVectorizer/X86/call.ll b/llvm/test/Transforms/SLPVectorizer/X86/call.ll
@@ -98,7 +98,7 @@ entry:
 
 
 ; CHECK: sqrt_libm
-; CHECK: call <2 x double> @llvm.sqrt.v2f64
+; CHECK: call nnan <2 x double> @llvm.sqrt.v2f64
 ; CHECK: ret void
 define void @sqrt_libm(double* %a, double* %b, double* %c) {
 entry:
diff --git a/llvm/test/Transforms/SLPVectorizer/X86/propagate_ir_flags.ll b/llvm/test/Transforms/SLPVectorizer/X86/propagate_ir_flags.ll
@@ -398,5 +398,42 @@ define void @fcmp_no_fast(double* %x) #1 {
   ret void
 }
 
-attributes #1 = { "target-features"="+avx" }
+declare double @llvm.fabs.f64(double) nounwind readnone
+
+;CHECK-LABEL: @call_fast(
+;CHECK: call fast <2 x double> @llvm.fabs.v2f64
+define void @call_fast(double* %x) {
+  %idx1 = getelementptr inbounds double, double* %x, i64 0
+  %idx2 = getelementptr inbounds double, double* %x, i64 1
+
+  %load1 = load double, double* %idx1, align 8
+  %load2 = load double, double* %idx2, align 8
+
+  %call1 = tail call fast double @llvm.fabs.f64(double %load1) nounwind readnone
+  %call2 = tail call fast double @llvm.fabs.f64(double %load2) nounwind readnone
+
+  store double %call1, double* %idx1, align 8
+  store double %call2, double* %idx2, align 8
+
+  ret void
+}
 
+;CHECK-LABEL: @call_no_fast(
+;CHECK: call <2 x double> @llvm.fabs.v2f64
+define void @call_no_fast(double* %x) {
+  %idx1 = getelementptr inbounds double, double* %x, i64 0
+  %idx2 = getelementptr inbounds double, double* %x, i64 1
+
+  %load1 = load double, double* %idx1, align 8
+  %load2 = load double, double* %idx2, align 8
+
+  %call1 = tail call fast double @llvm.fabs.f64(double %load1) nounwind readnone
+  %call2 = tail call double @llvm.fabs.f64(double %load2) nounwind readnone
+
+  store double %call1, double* %idx1, align 8
+  store double %call2, double* %idx2, align 8
+
+  ret void
+}
+
+attributes #1 = { "target-features"="+avx" }

Original file line number	Diff line number	Diff line change
`@@ -2641,6 +2641,7 @@ Value BoUpSLP::vectorizeTree(TreeEntry E) {`
`2641`	`2641`	`ExternalUses.push_back(ExternalUser(ScalarArg, cast<User>(V), 0));`
`2642`	`2642`
`2643`	`2643`	`E->VectorizedValue = V;`
	`2644`	`+ propagateIRFlags(E->VectorizedValue, E->Scalars);`
`2644`	`2645`	`++NumVectorInstructions;`
`2645`	`2646`	`return V;`
`2646`	`2647`	`}`