[llvm] [FuncSpec] Enable SpecializeLiteralConstant by default (PR #113442)

[Alexandros Lamprineas via llvm-commits]

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@@ -0,0 +1,147 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --include-generated-funcs --version 5
+; RUN: opt -passes="ipsccp<func-spec>" -force-specialization \
+; RUN:     -funcspec-max-iters=3 -S < %s | FileCheck %s
+
+; RUN: opt -passes="ipsccp<func-spec>" -force-specialization          \
+; RUN:     -funcspec-for-literal-constant=false -funcspec-max-iters=3 \
+; RUN:     -S < %s | FileCheck %s --check-prefix=NOLIT
+
+ at global_true = constant i1 true
+ at global_false = constant i1 false
+
+define i64 @main() {
+entry:
+  %binop1 = call ptr @select_binop(ptr @global_true)
+  %binop2 = call ptr @select_binop(ptr @global_false)
+
+  %c1 = call i64 @compute(ptr %binop1)
+  %c2 = call i64 @compute(ptr %binop2)
+  %add = add i64 %c1, %c2
+  ret i64 %add
+}
+
+define ptr @select_binop(ptr %flag) {
+  %flag.val = load i1, ptr %flag
+  %binop = select i1 %flag.val, ptr @plus, ptr @minus
+  ret ptr %binop
+}
+
+define internal i64 @compute(ptr %binop) {
+entry:
+  %res = call i64 %binop(i64 1, i64 1)
+  ret i64 %res
+}
+
+define internal i64 @plus(i64 %x) {
+entry:
+  %sum = add i64 %x, 1
+  ret i64 %sum
+}
+
+define internal i64 @minus(i64 %x) {
+entry:
+  %diff = sub i64 %x, 1
+  ret i64 %diff
+}
+; CHECK-LABEL: define i64 @main() {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[BINOP1:%.*]] = call ptr @select_binop.specialized.1(ptr @global_true)
+; CHECK-NEXT:    [[BINOP2:%.*]] = call ptr @select_binop.specialized.2(ptr @global_false)
+; CHECK-NEXT:    [[C1:%.*]] = call i64 @compute.specialized.3(ptr @plus)
+; CHECK-NEXT:    [[C2:%.*]] = call i64 @compute.specialized.4(ptr @minus)
+; CHECK-NEXT:    [[ADD:%.*]] = add i64 [[C1]], [[C2]]
----------------
labrinea wrote:

>From a quick debug I noticed that plus and minus are not considered for specialization because they have not yet replaced the binop in the body of compute.specialized.3 and compute.specialized.4 (the Solver only knowns their lattice value), therefore findSpecializations does not find these callsites in the users list.

https://github.com/llvm/llvm-project/pull/113442