[EarlyCSE] Precommit test for D153151

[foad]

Self-approving.

llvm/test/Transforms/EarlyCSE/AMDGPU/convergent-call.ll

+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 2
+; RUN: opt < %s -S -mtriple=amdgcn-- -passes=early-cse -earlycse-debug-hash | FileCheck %s
+
+; Should not CSE calls marked as convergent, even if the callee is not convergent.
+
+define i32 @test_read_register(i32 %cond) {
+; CHECK-LABEL: define i32 @test_read_register
+; CHECK-SAME: (i32 [[COND:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[X1:%.*]] = call i32 @llvm.read_register.i32(metadata [[META0:![0-9]+]]) #[[ATTR2:[0-9]+]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[COND]], 0
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
+; CHECK:       if:
+; CHECK-NEXT:    br label [[END]]
+; CHECK:       end:
+; CHECK-NEXT:    [[Y2:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[X1]], [[IF]] ]
+; CHECK-NEXT:    [[RET:%.*]] = add i32 [[X1]], [[Y2]]
+; CHECK-NEXT:    ret i32 [[RET]]
+;
+entry:
+  ; %x = ballot operation over all lanes.
+  %x1 = call i32 @llvm.read_register.i32(metadata !{!"exec_lo"}) convergent
+  %cmp = icmp eq i32 %cond, 0
+  br i1 %cmp, label %if, label %end
+
+if:
+  ; %y = ballot operation over lanes satisfying %cond.
+  %y1 = call i32 @llvm.read_register.i32(metadata !{!"exec_lo"}) convergent
+  br label %end
+
+end:
+  %y2 = phi i32 [0, %entry], [%y1, %if]
+  %ret = add i32 %x1, %y2
+  ret i32 %ret
+}
+
+define i32 @test_read_register_samebb(i32 %cond) {
+; CHECK-LABEL: define i32 @test_read_register_samebb
+; CHECK-SAME: (i32 [[COND:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.read_register.i32(metadata [[META0]]) #[[ATTR2]]
+; CHECK-NEXT:    [[RET:%.*]] = add i32 [[X]], [[X]]
+; CHECK-NEXT:    ret i32 [[RET]]
+;
+entry:
+  %x = call i32 @llvm.read_register.i32(metadata !{!"exec_lo"}) convergent
+  %y = call i32 @llvm.read_register.i32(metadata !{!"exec_lo"}) convergent
+  %ret = add i32 %x, %y
+  ret i32 %ret
+}
+
+define i1 @test_live_mask(i32 %cond) {
+; CHECK-LABEL: define i1 @test_live_mask
+; CHECK-SAME: (i32 [[COND:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[X1:%.*]] = call i1 @llvm.amdgcn.live.mask() #[[ATTR2]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[COND]], 0
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
+; CHECK:       if:
+; CHECK-NEXT:    br label [[END]]
+; CHECK:       end:
+; CHECK-NEXT:    [[Y2:%.*]] = phi i1 [ false, [[ENTRY:%.*]] ], [ [[X1]], [[IF]] ]
+; CHECK-NEXT:    [[RET:%.*]] = add i1 [[X1]], [[Y2]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+entry:
+  %x1 = call i1 @llvm.amdgcn.live.mask() convergent
+  %cmp = icmp eq i32 %cond, 0
+  br i1 %cmp, label %if, label %end
+
+if:
+  %y1 = call i1 @llvm.amdgcn.live.mask() convergent
+  br label %end
+
+end:
+  %y2 = phi i1 [0, %entry], [%y1, %if]
+  %ret = add i1 %x1, %y2
+  ret i1 %ret
+}
+
+declare i32 @llvm.read_register.i32(metadata)
+declare i1 @llvm.amdgcn.live.mask()