[llvm] [CGP] Undo constant propagation of pointers across calls (PR #102926)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,123 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -S -passes='require<profile-summary>,function(codegenprepare)' -mtriple=aarch64-none-linux-gnu < %s | FileCheck %s
+
+%struct.S = type { i8 }
+%struct.X = type { i32 }
+
+ at g_getS = internal global %struct.S zeroinitializer, align 1
+ at g_getX = internal global %struct.X zeroinitializer, align 1
+ at guard = internal global i64 0, align 8
+
+declare ptr @getS_dec()
+
+define nonnull align 1 dereferenceable(1) ptr @getS() personality ptr @__gxx_personality_v0 {
+entry:
+  %guard = load atomic i8, ptr @guard acquire, align 8
+  %mask = and i8 %guard, 1
+  %cond = icmp eq i8 %mask, 0
+  br i1 %cond, label %to_be_init, label %return
+
+to_be_init:                                       ; preds = %entry
+  %is_init = call i32 @__cxa_guard_acquire(ptr @guard)
+  %cond.2 = icmp ne i32 %is_init, 0
+  br i1 %cond.2, label %ctor, label %return
+
+ctor:                                             ; preds = %to_be_init
+  invoke void @S_ctor(ptr nonnull align 1 dereferenceable(1) @g_getS)
+  to label %continue unwind label %landing_pad
+
+continue:                                         ; preds = %ctor
+  call void @__cxa_guard_release(ptr @guard)
+  br label %return
+
+return:                                           ; preds = %continue, %to_be_init, %entry
+  ret ptr @g_getS
+
+landing_pad:                                      ; preds = %ctor
+  %lp = landingpad { ptr, i32 } cleanup
+  call void @__cxa_guard_abort(ptr @guard)
+  resume { ptr, i32 } %lp
+}
+
+define ptr @getS_or_getX(i1 %cond) {
+entry:
+  %result = select i1 %cond, ptr @g_getS, ptr @g_getX
+  ret ptr %result
+}
+
+define weak ptr @getS_weak_function() {
+entry:
+  ret ptr @g_getS
+}
+
+define available_externally dllimport ptr @getS_dllimport_function() {
+entry:
+  ret ptr @g_getS
+}
+
+; May revert propagation.
+define i32 @caller_1() {
+; CHECK-LABEL: @caller_1(
+; CHECK-NEXT:    [[GETS_PTR:%.*]] = call nonnull align 1 dereferenceable(1) ptr @getS()
+; CHECK-NEXT:    [[GETI:%.*]] = call i32 @S_getI(ptr nonnull align 1 dereferenceable(1) [[GETS_PTR]])
+; CHECK-NEXT:    ret i32 [[GETI]]
+;
+  %getS_ptr = call nonnull align 1 dereferenceable(1) ptr @getS()
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nikic wrote:

Remove unnecessary attributes here and elsewhere.

https://github.com/llvm/llvm-project/pull/102926