[InstSimplify] don't commute constant expression operand in min/max c…

…alls

The test shows that we would fail to consistently fold the
instruction based on the max value operand. This is also
the root cause for issue #57986, but I'll add an instcombine
test + assert for that exact problem in another commit.

llvm/lib/Analysis/InstructionSimplify.cpp

@@ -5843,8 +5843,8 @@ static Value *simplifyBinaryIntrinsic(Function *F, Value *Op0, Value *Op1,
     if (Op0 == Op1)
       return Op0;
 
-    // Canonicalize constant operand as Op1.
-    if (isa<Constant>(Op0))
+    // Canonicalize immediate constant operand as Op1.
+    if (match(Op0, m_ImmConstant()))
       std::swap(Op0, Op1);
 
     // Assume undef is the limit value.

llvm/test/Transforms/InstSimplify/maxmin_intrinsics.ll

@@ -27,8 +27,7 @@ define i8 @constexpr_maxvalue() {
 
 define i8 @constexpr_maxvalue_commute() {
 ; CHECK-LABEL: @constexpr_maxvalue_commute(
-; CHECK-NEXT:    [[UMIN:%.*]] = call i8 @llvm.umin.i8(i8 ptrtoint (ptr @g to i8), i8 -1)
-; CHECK-NEXT:    ret i8 [[UMIN]]
+; CHECK-NEXT:    ret i8 ptrtoint (ptr @g to i8)
 ;
   %umin = call i8 @llvm.umin.i8(i8 ptrtoint (ptr @g to i8), i8 255)
   ret i8 %umin