[FuncSpec] Precommit test for looking through llvm.ssa.copy

Author: hazzlim

llvm/test/Transforms/FunctionSpecialization/ssa-copy.ll

@@ -0,0 +1,67 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --include-generated-funcs --version 5
+; RUN: opt -passes="ipsccp<func-spec>" -funcspec-min-function-size=1       \
+; RUN:                                 -funcspec-for-literal-constant=true \
+; RUN:                                 -funcspec-min-codesize-savings=50   \
+; RUN:                                 -funcspec-min-latency-savings=0     \
+; RUN:                                 -S < %s | FileCheck %s
+
+; Verify that we are able to estimate the codesize savings by looking through
+; calls to ssa_copy intrinsics, which are inserted by PredicateInfo when IPSCCP
+; is run prior to FunctionSpecialization.
+; FIXME: We should be able to specialize this, but we currently do not handle
+; FIXME: llvm.ssa.copy calls in InstCostVisitor.
+define i32 @main() {
+entry:
+  %res = call i32 @test_ssa_copy(i32 0)
+  ret i32 %res
+}
+
+define i32 @test_ssa_copy(i32 %x) {
+entry:
+  br label %block1
+
+block1:
+  %cmp = icmp eq i32 %x, 0
+  br i1 %cmp, label %block2, label %exit1
+
+block2:
+  br i1 %cmp, label %block3, label %exit2
+
+block3:
+  br i1 %cmp, label %exit4, label %exit3
+
+exit1:
+  ret i32 %x
+
+exit2:
+  ret i32 %x
+
+exit3:
+  ret i32 %x
+
+exit4:
+  ret i32 999
+}
+
+; CHECK-LABEL: define range(i32 1, 0) i32 @main() {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[RES:%.*]] = call i32 @test_ssa_copy(i32 0)
+; CHECK-NEXT:    ret i32 [[RES]]
+;
+;
+; CHECK-LABEL: define range(i32 1, 0) i32 @test_ssa_copy(
+; CHECK-SAME: i32 [[X:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    br label %[[BLOCK1:.*]]
+; CHECK:       [[BLOCK1]]:
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[X]], 0
+; CHECK-NEXT:    br i1 [[CMP]], label %[[BLOCK2:.*]], label %[[EXIT1:.*]]
+; CHECK:       [[BLOCK2]]:
+; CHECK-NEXT:    br label %[[BLOCK3:.*]]
+; CHECK:       [[BLOCK3]]:
+; CHECK-NEXT:    br label %[[EXIT4:.*]]
+; CHECK:       [[EXIT1]]:
+; CHECK-NEXT:    ret i32 [[X]]
+; CHECK:       [[EXIT4]]:
+; CHECK-NEXT:    ret i32 999
+;