91c9dee3fb
CodeGenPrepare currently first removes empty blocks, then in a loop performs other optimizations. One of those optimizations is the removal of call instructions that invoke @llvm.assume, which can create new empty blocks. This means that when a branch only contains a call to __builtin_assume(), the empty branch will survive into MIR, and will then only be half-removed by MIR-level optimizations (e.g. removing the branch but leaving the condition intact). Fix it by eliminating @llvm.expect builtin calls before removing empty blocks. Reviewed By: bkramer Differential Revision: https://reviews.llvm.org/D97848
31 lines
893 B
LLVM
31 lines
893 B
LLVM
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
|
|
; RUN: opt -codegenprepare -S -mtriple=x86_64-linux < %s | FileCheck %s
|
|
|
|
define i32 @test1(i8* %d) nounwind {
|
|
; CHECK-LABEL: @test1(
|
|
; CHECK-NEXT: entry:
|
|
; CHECK-NEXT: [[L:%.*]] = load i8, i8* [[D:%.*]], align 1
|
|
; CHECK-NEXT: [[TMP0:%.*]] = icmp eq i8 [[L]], 0
|
|
; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[TMP0]] to i32
|
|
; CHECK-NEXT: ret i32 [[CONV]]
|
|
;
|
|
entry:
|
|
%l = load i8, i8* %d
|
|
%cmp = icmp eq i8 %l, 0
|
|
br i1 %cmp, label %exit, label %if.end
|
|
|
|
if.end:
|
|
%gep = getelementptr i8, i8* %d, i32 42
|
|
%call = call i64 @foo(i8* %gep) nounwind readonly willreturn
|
|
%cmp2 = icmp ne i64 %call, 0
|
|
call void @llvm.assume(i1 %cmp2)
|
|
br label %exit
|
|
|
|
exit:
|
|
%conv = zext i1 %cmp to i32
|
|
ret i32 %conv
|
|
}
|
|
|
|
declare i64 @foo(i8*) nounwind readonly willreturn
|
|
declare void @llvm.assume(i1 noundef) nounwind willreturn
|