[llvm] [ValueTracking] Propagate sign information out of loop (PR #175590)

[Kshitij Paranjape via llvm-commits]

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@@ -0,0 +1,185 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
+; RUN: opt < %s -passes=aggressive-instcombine -S | FileCheck %s
+target triple = "x86_64-unknown-linux-gnu"
+define double @CompareDistmats(double noundef %distmat1_, double noundef %distmat2_) {
+; CHECK-LABEL: define double @CompareDistmats(
+; CHECK-SAME: double noundef [[DISTMAT1_:%.*]], double noundef [[DISTMAT2_:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    br label %[[FOR_COND:.*]]
+; CHECK:       [[FOR_COND]]:
+; CHECK-NEXT:    [[RMSD_0:%.*]] = phi double [ 0.000000e+00, %[[ENTRY]] ], [ [[FMACALL:%.*]], %[[FOR_BODY:.*]] ]
+; CHECK-NEXT:    [[CMP:%.*]] = phi i1 [ true, %[[ENTRY]] ], [ false, %[[FOR_BODY]] ]
+; CHECK-NEXT:    br i1 [[CMP]], label %[[FOR_BODY]], label %[[FOR_COND_CLEANUP:.*]]
+; CHECK:       [[FOR_COND_CLEANUP]]:
+; CHECK-NEXT:    [[SQRT:%.*]] = call double @llvm.sqrt.f64(double [[RMSD_0]])
+; CHECK-NEXT:    ret double [[SQRT]]
+; CHECK:       [[FOR_BODY]]:
+; CHECK-NEXT:    [[SUB:%.*]] = fsub double [[DISTMAT1_]], [[DISTMAT2_]]
+; CHECK-NEXT:    [[FMACALL]] = call double @llvm.fmuladd.f64(double noundef [[SUB]], double noundef [[SUB]], double [[RMSD_0]])
+; CHECK-NEXT:    br label %[[FOR_COND]]
+;
+entry:
+  br label %for.cond
+
+for.cond:                                         ; preds = %for.body, %entry
+  %RMSD.0 = phi double [ 0.000000e+00, %entry ], [ %fmacall, %for.body ]
+  %cmp = phi i1 [ true, %entry ], [ false, %for.body ]
+  br i1 %cmp, label %for.body, label %for.cond.cleanup
+
+for.cond.cleanup:                                 ; preds = %for.cond
+  %call = call double @sqrt(double noundef %RMSD.0)
+  ret double %call
+
+for.body:                                         ; preds = %for.cond
+  %sub = fsub double %distmat1_, %distmat2_
+  %fmacall = call double @llvm.fmuladd.f64(double noundef %sub, double noundef %sub, double %RMSD.0)
+  br label %for.cond
+}
+
+define double @fmaCompareDistmats(double noundef %distmat1_, double noundef %distmat2_) {
+; CHECK-LABEL: define double @fmaCompareDistmats(
+; CHECK-SAME: double noundef [[DISTMAT1_:%.*]], double noundef [[DISTMAT2_:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*]]:
+; CHECK-NEXT:    br label %[[FOR_COND:.*]]
+; CHECK:       [[FOR_COND]]:
+; CHECK-NEXT:    [[RMSD_0:%.*]] = phi double [ 0.000000e+00, %[[ENTRY]] ], [ [[FMACALL:%.*]], %[[FOR_BODY:.*]] ]
+; CHECK-NEXT:    [[CMP:%.*]] = phi i1 [ true, %[[ENTRY]] ], [ false, %[[FOR_BODY]] ]
+; CHECK-NEXT:    br i1 [[CMP]], label %[[FOR_BODY]], label %[[FOR_COND_CLEANUP:.*]]
+; CHECK:       [[FOR_COND_CLEANUP]]:
+; CHECK-NEXT:    [[SQRT:%.*]] = call double @llvm.sqrt.f64(double [[RMSD_0]])
+; CHECK-NEXT:    ret double [[SQRT]]
+; CHECK:       [[FOR_BODY]]:
+; CHECK-NEXT:    [[SUB:%.*]] = fsub double [[DISTMAT1_]], [[DISTMAT2_]]
+; CHECK-NEXT:    [[FMACALL]] = call double @llvm.fma.f64(double [[SUB]], double [[SUB]], double [[RMSD_0]])
+; CHECK-NEXT:    br label %[[FOR_COND]]
+;
+entry:
+  br label %for.cond
+
+for.cond:                                         ; preds = %for.body, %entry
+  %RMSD.0 = phi double [ 0.000000e+00, %entry ], [ %fmacall, %for.body ]
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kshitijvp wrote:

Done

https://github.com/llvm/llvm-project/pull/175590