PredicateInfo: Handle critical edges

Summary:
This adds support for placing predicateinfo such that it affects critical edges.

This fixes the issues mentioned by Nuno on the mailing list.

Depends on D29519

Reviewers: davide, nlopes

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29606

llvm-svn: 294921

1 files changed, 241 insertions, 0 deletions

diff --git a/llvm/test/Transforms/Util/PredicateInfo/edge.ll b/llvm/test/Transforms/Util/PredicateInfo/edge.ll
new file mode 100644
index 00000000000..5f400ccb795
--- /dev/null
+++ b/llvm/test/Transforms/Util/PredicateInfo/edge.ll
@@ -0,0 +1,241 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -print-predicateinfo -analyze  < %s 2>&1 | FileCheck %s
+
+define i32 @f1(i32 %x) {
+; CHECK-LABEL: @f1(
+; CHECK-NEXT:  bb0:
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[X:%.*]], 0
+; CHECK:         [[X_0:%.*]] = call i32 @llvm.ssa.copy.i32(i32 [[X]])
+; CHECK-NEXT:    br i1 [[CMP]], label [[BB2:%.*]], label [[BB1:%.*]]
+; CHECK:       bb1:
+; CHECK-NEXT:    br label [[BB2]]
+; CHECK:       bb2:
+; CHECK-NEXT:    [[COND:%.*]] = phi i32 [ [[X_0]], [[BB0:%.*]] ], [ 0, [[BB1]] ]
+; CHECK-NEXT:    [[FOO:%.*]] = add i32 [[COND]], [[X]]
+; CHECK-NEXT:    ret i32 [[FOO]]
+;
+bb0:
+  %cmp = icmp eq i32 %x, 0
+  br i1 %cmp, label %bb2, label %bb1
+bb1:
+  br label %bb2
+bb2:
+  %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
+  %foo = add i32 %cond, %x
+  ret i32 %foo
+}
+
+define i32 @f2(i32 %x) {
+; CHECK-LABEL: @f2(
+; CHECK-NEXT:  bb0:
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ne i32 [[X:%.*]], 0
+; CHECK:         [[X_0:%.*]] = call i32 @llvm.ssa.copy.i32(i32 [[X]])
+; CHECK-NEXT:    br i1 [[CMP]], label [[BB1:%.*]], label [[BB2:%.*]]
+; CHECK:       bb1:
+; CHECK-NEXT:    br label [[BB2]]
+; CHECK:       bb2:
+; CHECK-NEXT:    [[COND:%.*]] = phi i32 [ [[X_0]], [[BB0:%.*]] ], [ 0, [[BB1]] ]
+; CHECK-NEXT:    [[FOO:%.*]] = add i32 [[COND]], [[X]]
+; CHECK-NEXT:    ret i32 [[FOO]]
+;
+bb0:
+  %cmp = icmp ne i32 %x, 0
+  br i1 %cmp, label %bb1, label %bb2
+bb1:
+  br label %bb2
+bb2:
+  %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
+  %foo = add i32 %cond, %x
+  ret i32 %foo
+}
+
+define i32 @f3(i32 %x) {
+; CHECK-LABEL: @f3(
+; CHECK-NEXT:  bb0:
+; CHECK-NEXT:    switch i32 [[X:%.*]], label [[BB1:%.*]] [
+; CHECK-NEXT:    i32 0, label [[BB2:%.*]]
+; CHECK-NEXT:    ]
+; CHECK:       bb1:
+; CHECK-NEXT:    br label [[BB2]]
+; CHECK:       bb2:
+; CHECK-NEXT:    [[COND:%.*]] = phi i32 [ [[X]], [[BB0:%.*]] ], [ 0, [[BB1]] ]
+; CHECK-NEXT:    [[FOO:%.*]] = add i32 [[COND]], [[X]]
+; CHECK-NEXT:    ret i32 [[FOO]]
+;
+bb0:
+  switch i32 %x, label %bb1 [ i32 0, label %bb2]
+bb1:
+  br label %bb2
+bb2:
+  %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
+  %foo = add i32 %cond, %x
+  ret i32 %foo
+}
+
+
+define double @fcmp_oeq_not_zero(double %x, double %y) {
+; CHECK-LABEL: @fcmp_oeq_not_zero(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CMP:%.*]] = fcmp oeq double [[Y:%.*]], 2.000000e+00
+; CHECK:         [[Y_0:%.*]] = call double @llvm.ssa.copy.f64(double [[Y]])
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF:%.*]], label [[RETURN:%.*]]
+; CHECK:       if:
+; CHECK-NEXT:    [[DIV:%.*]] = fdiv double [[X:%.*]], [[Y_0]]
+; CHECK-NEXT:    br label [[RETURN]]
+; CHECK:       return:
+; CHECK-NEXT:    [[RETVAL:%.*]] = phi double [ [[DIV]], [[IF]] ], [ [[X]], [[ENTRY:%.*]] ]
+; CHECK-NEXT:    ret double [[RETVAL]]
+;
+entry:
+  %cmp = fcmp oeq double %y, 2.0
+  br i1 %cmp, label %if, label %return
+
+if:
+  %div = fdiv double %x, %y
+  br label %return
+
+return:
+  %retval = phi double [ %div, %if ], [ %x, %entry ]
+  ret double %retval
+
+}
+
+define double @fcmp_une_not_zero(double %x, double %y) {
+; CHECK-LABEL: @fcmp_une_not_zero(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CMP:%.*]] = fcmp une double [[Y:%.*]], 2.000000e+00
+; CHECK:         [[Y_0:%.*]] = call double @llvm.ssa.copy.f64(double [[Y]])
+; CHECK-NEXT:    br i1 [[CMP]], label [[RETURN:%.*]], label [[ELSE:%.*]]
+; CHECK:       else:
+; CHECK-NEXT:    [[DIV:%.*]] = fdiv double [[X:%.*]], [[Y_0]]
+; CHECK-NEXT:    br label [[RETURN]]
+; CHECK:       return:
+; CHECK-NEXT:    [[RETVAL:%.*]] = phi double [ [[DIV]], [[ELSE]] ], [ [[X]], [[ENTRY:%.*]] ]
+; CHECK-NEXT:    ret double [[RETVAL]]
+;
+entry:
+  %cmp = fcmp une double %y, 2.0
+  br i1 %cmp, label %return, label %else
+
+else:
+  %div = fdiv double %x, %y
+  br label %return
+
+return:
+  %retval = phi double [ %div, %else ], [ %x, %entry ]
+  ret double %retval
+
+}
+
+define double @fcmp_oeq_zero(double %x, double %y) {
+; CHECK-LABEL: @fcmp_oeq_zero(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CMP:%.*]] = fcmp oeq double [[Y:%.*]], 0.000000e+00
+; CHECK:         [[Y_0:%.*]] = call double @llvm.ssa.copy.f64(double [[Y]])
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF:%.*]], label [[RETURN:%.*]]
+; CHECK:       if:
+; CHECK-NEXT:    [[DIV:%.*]] = fdiv double [[X:%.*]], [[Y_0]]
+; CHECK-NEXT:    br label [[RETURN]]
+; CHECK:       return:
+; CHECK-NEXT:    [[RETVAL:%.*]] = phi double [ [[DIV]], [[IF]] ], [ [[X]], [[ENTRY:%.*]] ]
+; CHECK-NEXT:    ret double [[RETVAL]]
+;
+entry:
+  %cmp = fcmp oeq double %y, 0.0
+  br i1 %cmp, label %if, label %return
+
+if:
+  %div = fdiv double %x, %y
+  br label %return
+
+return:
+  %retval = phi double [ %div, %if ], [ %x, %entry ]
+  ret double %retval
+
+}
+
+define double @fcmp_une_zero(double %x, double %y) {
+; CHECK-LABEL: @fcmp_une_zero(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CMP:%.*]] = fcmp une double [[Y:%.*]], -0.000000e+00
+; CHECK:         [[Y_0:%.*]] = call double @llvm.ssa.copy.f64(double [[Y]])
+; CHECK-NEXT:    br i1 [[CMP]], label [[RETURN:%.*]], label [[ELSE:%.*]]
+; CHECK:       else:
+; CHECK-NEXT:    [[DIV:%.*]] = fdiv double [[X:%.*]], [[Y_0]]
+; CHECK-NEXT:    br label [[RETURN]]
+; CHECK:       return:
+; CHECK-NEXT:    [[RETVAL:%.*]] = phi double [ [[DIV]], [[ELSE]] ], [ [[X]], [[ENTRY:%.*]] ]
+; CHECK-NEXT:    ret double [[RETVAL]]
+;
+entry:
+  %cmp = fcmp une double %y, -0.0
+  br i1 %cmp, label %return, label %else
+
+else:
+  %div = fdiv double %x, %y
+  br label %return
+
+return:
+  %retval = phi double [ %div, %else ], [ %x, %entry ]
+  ret double %retval
+
+}
+
+
+define double @fcmp_oeq_maybe_zero(double %x, double %y, double %z1, double %z2) {
+; CHECK-LABEL: @fcmp_oeq_maybe_zero(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[Z:%.*]] = fadd double [[Z1:%.*]], [[Z2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = fcmp oeq double [[Y:%.*]], [[Z]]
+; CHECK:         [[Z_0:%.*]] = call double @llvm.ssa.copy.f64(double [[Z]])
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF:%.*]], label [[RETURN:%.*]]
+; CHECK:       if:
+; CHECK-NEXT:    [[DIV:%.*]] = fdiv double [[X:%.*]], [[Z_0]]
+; CHECK-NEXT:    br label [[RETURN]]
+; CHECK:       return:
+; CHECK-NEXT:    [[RETVAL:%.*]] = phi double [ [[DIV]], [[IF]] ], [ [[X]], [[ENTRY:%.*]] ]
+; CHECK-NEXT:    ret double [[RETVAL]]
+;
+entry:
+  %z = fadd double %z1, %z2
+  %cmp = fcmp oeq double %y, %z
+  br i1 %cmp, label %if, label %return
+
+if:
+  %div = fdiv double %x, %z
+  br label %return
+
+return:
+  %retval = phi double [ %div, %if ], [ %x, %entry ]
+  ret double %retval
+
+}
+
+define double @fcmp_une_maybe_zero(double %x, double %y, double %z1, double %z2) {
+; CHECK-LABEL: @fcmp_une_maybe_zero(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[Z:%.*]] = fadd double [[Z1:%.*]], [[Z2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = fcmp une double [[Y:%.*]], [[Z]]
+; CHECK:         [[Z_0:%.*]] = call double @llvm.ssa.copy.f64(double [[Z]])
+; CHECK-NEXT:    br i1 [[CMP]], label [[RETURN:%.*]], label [[ELSE:%.*]]
+; CHECK:       else:
+; CHECK-NEXT:    [[DIV:%.*]] = fdiv double [[X:%.*]], [[Z_0]]
+; CHECK-NEXT:    br label [[RETURN]]
+; CHECK:       return:
+; CHECK-NEXT:    [[RETVAL:%.*]] = phi double [ [[DIV]], [[ELSE]] ], [ [[X]], [[ENTRY:%.*]] ]
+; CHECK-NEXT:    ret double [[RETVAL]]
+;
+entry:
+  %z = fadd double %z1, %z2
+  %cmp = fcmp une double %y, %z
+  br i1 %cmp, label %return, label %else
+
+else:
+  %div = fdiv double %x, %z
+  br label %return
+
+return:
+  %retval = phi double [ %div, %else ], [ %x, %entry ]
+  ret double %retval
+
+}