mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-23 11:13:28 +01:00
ca6b59008b
Summary: Currently we express umin as `~umax(~x, ~y)`. However, this becomes a problem for operands in non-integral pointer spaces, because `~x` is not something we can compute for `x` non-integral. However, since comparisons are generally still allowed, we are actually able to express `umin(x, y)` directly as long as we don't try to express is as a umax. Support this by adding an explicit umin/smin representation to SCEV. We do this by factoring the existing getUMax/getSMax functions into a new function that does all four. The previous two functions were largely identical. Reviewed By: sanjoy Differential Revision: https://reviews.llvm.org/D50167 llvm-svn: 360159
54 lines
1.8 KiB
LLVM
54 lines
1.8 KiB
LLVM
; RUN: opt -scalar-evolution -analyze < %s | FileCheck %s
|
|
;
|
|
; This checks if the min and max expressions are properly recognized by
|
|
; ScalarEvolution even though they the ICmpInst and SelectInst have different
|
|
; types.
|
|
;
|
|
; #define max(a, b) (a > b ? a : b)
|
|
; #define min(a, b) (a < b ? a : b)
|
|
;
|
|
; void f(int *A, int N) {
|
|
; for (int i = 0; i < N; i++) {
|
|
; A[max(0, i - 3)] = A[min(N, i + 3)] * 2;
|
|
; }
|
|
; }
|
|
;
|
|
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
|
|
|
|
define void @f(i32* %A, i32 %N) {
|
|
bb:
|
|
br label %bb1
|
|
|
|
bb1: ; preds = %bb2, %bb
|
|
%i.0 = phi i32 [ 0, %bb ], [ %tmp23, %bb2 ]
|
|
%i.0.1 = sext i32 %i.0 to i64
|
|
%tmp = icmp slt i32 %i.0, %N
|
|
br i1 %tmp, label %bb2, label %bb24
|
|
|
|
bb2: ; preds = %bb1
|
|
%tmp3 = add nuw nsw i32 %i.0, 3
|
|
%tmp4 = icmp slt i32 %tmp3, %N
|
|
%tmp5 = sext i32 %tmp3 to i64
|
|
%tmp6 = sext i32 %N to i64
|
|
%tmp9 = select i1 %tmp4, i64 %tmp5, i64 %tmp6
|
|
; min(N, i+3)
|
|
; CHECK: select i1 %tmp4, i64 %tmp5, i64 %tmp6
|
|
; CHECK-NEXT: --> ((sext i32 {3,+,1}<nuw><%bb1> to i64) smin (sext i32 %N to i64))
|
|
%tmp11 = getelementptr inbounds i32, i32* %A, i64 %tmp9
|
|
%tmp12 = load i32, i32* %tmp11, align 4
|
|
%tmp13 = shl nsw i32 %tmp12, 1
|
|
%tmp14 = icmp sge i32 3, %i.0
|
|
%tmp17 = add nsw i64 %i.0.1, -3
|
|
%tmp19 = select i1 %tmp14, i64 0, i64 %tmp17
|
|
; max(0, i - 3)
|
|
; CHECK: select i1 %tmp14, i64 0, i64 %tmp17
|
|
; CHECK-NEXT: --> (-3 + (3 smax {0,+,1}<nuw><nsw><%bb1>))
|
|
%tmp21 = getelementptr inbounds i32, i32* %A, i64 %tmp19
|
|
store i32 %tmp13, i32* %tmp21, align 4
|
|
%tmp23 = add nuw nsw i32 %i.0, 1
|
|
br label %bb1
|
|
|
|
bb24: ; preds = %bb1
|
|
ret void
|
|
}
|