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| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -simplifycfg -S | FileCheck %s --check-prefixes=ALL,DEFAULT,FALLBACK0
; RUN: opt < %s -simplifycfg -phi-node-folding-threshold=2 -S | FileCheck %s --check-prefixes=ALL,DEFAULT,FALLBACK1
; RUN: opt < %s -simplifycfg -phi-node-folding-threshold=3 -S | FileCheck %s --check-prefixes=ALL,COSTLY
; This is checking that the multiplication does overflow, with a leftover
; guard against division-by-zero that was needed before InstCombine
; produced llvm.umul.with.overflow.
define i1 @will_overflow(i64 %size, i64 %nmemb) {
; ALL-LABEL: @will_overflow(
; ALL-NEXT: entry:
; ALL-NEXT: [[CMP:%.*]] = icmp eq i64 [[SIZE:%.*]], 0
; ALL-NEXT: [[UMUL:%.*]] = tail call { i64, i1 } @llvm.umul.with.overflow.i64(i64 [[SIZE]], i64 [[NMEMB:%.*]])
; ALL-NEXT: [[UMUL_OV:%.*]] = extractvalue { i64, i1 } [[UMUL]], 1
; ALL-NEXT: [[UMUL_NOT_OV:%.*]] = xor i1 [[UMUL_OV]], true
; ALL-NEXT: [[TMP0:%.*]] = select i1 [[CMP]], i1 true, i1 [[UMUL_NOT_OV]]
; ALL-NEXT: ret i1 [[TMP0]]
;
entry:
%cmp = icmp eq i64 %size, 0
br i1 %cmp, label %land.end, label %land.rhs
land.rhs: ; preds = %entry
%umul = tail call { i64, i1 } @llvm.umul.with.overflow.i64(i64 %size, i64 %nmemb)
%umul.ov = extractvalue { i64, i1 } %umul, 1
%umul.not.ov = xor i1 %umul.ov, true
br label %land.end
land.end: ; preds = %land.rhs, %entry
%0 = phi i1 [ true, %entry ], [ %umul.not.ov, %land.rhs ]
ret i1 %0
}
; Function Attrs: nounwind readnone speculatable
declare { i64, i1 } @llvm.umul.with.overflow.i64(i64, i64) #0
|